U.S. patent application number 16/071341 was filed with the patent office on 2020-05-28 for rubbery polymer, graft copolymer, and thermoplastic resin composition.
The applicant listed for this patent is UMG ABS, LTD.. Invention is credited to Takashi IWANAGA, Yoshitaka NAITO.
Application Number | 20200165370 16/071341 |
Document ID | / |
Family ID | 59362406 |
Filed Date | 2020-05-28 |
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United States Patent
Application |
20200165370 |
Kind Code |
A1 |
IWANAGA; Takashi ; et
al. |
May 28, 2020 |
RUBBERY POLYMER, GRAFT COPOLYMER, AND THERMOPLASTIC RESIN
COMPOSITION
Abstract
A graft copolymer has good moldability and good continuous
moldability, and a thermoplastic resin molded article having
excellent impact resistance can be produced. A method can produce
the graft copolymer. A graft copolymer (B-I) produced by grafting
at least one vinyl monomer (b-I) selected from the group consisting
of an aromatic vinyl, an alkyl (meth)acrylate, and a vinyl cyanide
to a rubbery polymer mixture including a rubbery polymer (A-I) and
a hydrophobic substance, the rubbery polymer (A-I) including an
alkyl (meth)acrylate unit and a multifunctional monomer unit
copolymerizable with the alkyl (meth)acrylate, the hydrophobic
substance having a kinematic viscosity of 5 mm.sup.2/s or more at
40.degree. C. or a kinematic viscosity of 2 to 4 mm.sup.2/s at
100.degree. C., a principal constituent of the hydrophobic
substance being a hydrocarbon. A thermoplastic resin composition
includes the graft copolymer (B-I). A molded article produced uses
the thermoplastic resin composition.
Inventors: |
IWANAGA; Takashi; (Ube-shi,
Yamaguchi, JP) ; NAITO; Yoshitaka; (Ube-shi,
Yamaguchi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UMG ABS, LTD. |
Tokyo |
|
JP |
|
|
Family ID: |
59362406 |
Appl. No.: |
16/071341 |
Filed: |
January 18, 2017 |
PCT Filed: |
January 18, 2017 |
PCT NO: |
PCT/JP2017/001529 |
371 Date: |
July 19, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08L 51/04 20130101;
C08F 265/04 20130101; C08L 25/12 20130101; C08F 265/06 20130101;
C08L 33/20 20130101; C08F 265/04 20130101; C08L 25/12 20130101;
C08F 265/04 20130101; C08F 220/18 20130101; C08F 212/08 20130101;
C08F 2/22 20130101; C08F 2/22 20130101; C08F 220/1804 20200201;
C08F 222/102 20200201; C08F 220/1809 20200201; C08F 212/08
20130101; C08L 51/04 20130101; C08L 51/04 20130101; C08F 220/44
20130101; C08F 220/40 20130101 |
International
Class: |
C08F 265/06 20060101
C08F265/06; C08F 2/22 20060101 C08F002/22; C08F 220/18 20060101
C08F220/18; C08F 212/08 20060101 C08F212/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 21, 2016 |
JP |
2016-009798 |
Mar 25, 2016 |
JP |
2016-062085 |
Mar 25, 2016 |
JP |
2016-062086 |
Claims
1. A graft copolymer (B-I) produced by grafting at least one vinyl
monomer (b-I) selected from the group consisting of an aromatic
vinyl, an alkyl (meth)acrylate, and a vinyl cyanide to a rubbery
polymer mixture including a rubbery polymer (A-I) and a hydrophobic
substance, the rubbery polymer (A-I) including an alkyl
(meth)acrylate unit and a multifunctional monomer unit
copolymerizable with an alkyl (meth)acrylate, the hydrophobic
substance having a kinematic viscosity of 5 mm.sup.2/s or more at
40.degree. C. or a kinematic viscosity of 2 to 4 mm.sup.2/s at
100.degree. C., a principal constituent of the hydrophobic
substance being a hydrocarbon.
2. The graft copolymer (B-I) according to claim 1, wherein the
amount of the multifunctional monomer unit is 0.1 to 5.0 parts by
mass relative to 100 parts by mass of the total amount of the alkyl
(meth)acrylate unit and the multifunctional monomer unit.
3. The graft copolymer (B-I) according to claim 1, wherein the
ratio between the rubbery polymer (A-I) and the vinyl monomer (b-I)
is such that the proportion of the rubbery polymer (A-I) is 10% to
90% by mass and the proportion of the vinyl monomer (b-I) is 90% to
10% by mass (with the total proportion of the rubbery polymer (A-I)
and the vinyl monomer (b-I) being 100% by mass).
4. The graft copolymer (B-I) according to claim 1, wherein the
rubbery polymer mixture is a polymerization product produced by
polymerizing a miniemulsion containing the alkyl (meth)acrylate,
the multifunctional monomer, the hydrophobic substance, an
emulsifier, and water.
5. The graft copolymer (B-I) according to claim 4, wherein the
amount of the hydrophobic substance is 0.1 to 10 parts by mass
relative to 100 parts by mass of the alkyl (meth)acrylate.
6. The graft copolymer (B-I) according to claim 4, wherein the
rubbery polymer (A-I) included in the polymerization product has a
volume-average particle size of less than 1000 nm.
7. A thermoplastic resin composition comprising the graft copolymer
(B-I) according to claim 1.
8. A molded article produced using the thermoplastic resin
composition according to claim 7.
9. A method for producing a rubbery polymer (A-I), the method
comprising a miniemulsion formation step in which a mixture (a-I)
containing an alkyl (meth)acrylate, a multifunctional monomer
copolymerizable with the alkyl (meth)acrylate, a hydrophobic
substance, an emulsifier, and water is formed into a miniemulsion,
the hydrophobic substance having a kinematic viscosity of 5
mm.sup.2/s or more at 40.degree. C. or a kinematic viscosity of 2
to 4 mm.sup.2/s at 100.degree. C., a principal constituent of the
hydrophobic substance being a hydrocarbon, and a polymerization
step in which the miniemulsion is polymerized.
10. A method for producing a graft copolymer (B-I), the method
comprising grafting at least one vinyl monomer (b-I) selected from
the group consisting of an aromatic vinyl, an alkyl (meth)acrylate,
and a vinyl cyanide to a rubbery polymer (A-I) produced by the
method for producing a rubbery polymer (A-I) according to claim
9.
11. A method for producing a thermoplastic resin composition, the
method comprising using a graft copolymer (B-I) produced by the
method for producing a graft copolymer (B-I) according to claim
10.
12. A method for producing a molded article, the method comprising
using a thermoplastic resin composition produced by the method for
producing a thermoplastic resin composition according to claim
11.
13. A method for producing a graft copolymer (B-II), the method
comprising a miniemulsion formation step in which a mixture (a-II)
containing an alkyl (meth)acrylate, a multifunctional monomer
copolymerizable with the alkyl (meth)acrylate, an oil-soluble
initiator having 16 or more carbon atoms, an emulsifier, and water
is formed into a miniemulsion, a polymerization step in which the
miniemulsion is polymerized to form a rubbery polymer (A-II), and a
graft polymerization step in which at least one vinyl monomer
(b-II) selected from the group consisting of an aromatic vinyl, an
alkyl (meth)acrylate, and a vinyl cyanide is grafted to the rubbery
polymer (A-II) in order to produce a graft copolymer (B-II).
14. The method for producing a graft copolymer (B-II) according to
claim 13, wherein the amount of the multifunctional monomer is 0.1
to 5.0 parts by mass relative to 100 parts by mass of the total
amount of the alkyl (meth)acrylate and the multifunctional
monomer.
15. The method for producing a graft copolymer (B-II) according to
claim 13, wherein the ratio between the rubbery polymer (A-II) and
the vinyl monomer (b-II) is such that the proportion of the rubbery
polymer (A-II) is 10% to 90% by mass and the proportion of the
vinyl monomer (b-II) is 90% to 10% by mass (with the total
proportion of the rubbery polymer (A-II) and the vinyl monomer
(b-II) being 100% by mass).
16. The method for producing a graft copolymer (B-II) according to
claim 13, wherein the amount of the oil-soluble initiator used is
0.001 to 5 parts by mass relative to 100 parts by mass of the alkyl
(meth)acrylate.
17. The method for producing a graft copolymer (B-II) according to
claim 13, wherein the amount of the emulsifier used is 0.01 to 1.0
parts by mass relative to 100 parts by mass of the alkyl
(meth)acrylate.
18. A method for producing a thermoplastic resin composition, the
method comprising using a graft copolymer (B-II) produced by the
production method according to claim 13.
19. A method for producing a molded article, the method comprising
molding a thermoplastic resin composition produced by the
production method according to claim 18.
20. A graft copolymer (B-II) produced by grafting at least one
vinyl monomer (b-II) selected from the group consisting of an
aromatic vinyl, an alkyl (meth)acrylate, and a vinyl cyanide to a
rubbery polymer (A-II) produced by miniemulsion polymerization of a
mixture (a-II) containing an alkyl (meth)acrylate, a
multifunctional monomer copolymerizable with the alkyl
(meth)acrylate, an oil-soluble initiator having 16 or more carbon
atoms, an emulsifier, and water.
21. A thermoplastic resin composition comprising the graft
copolymer (B-II) according to claim 20.
22. A molded article produced by molding the thermoplastic resin
composition according to claim 21.
23. A graft copolymer (B-III) comprising a rubbery polymer (A-III)
and a graft layer (g), the rubbery polymer (A-III) being a
polymerization product produced by polymerizing a pre-emulsion
containing an alkyl (meth)acrylate, a multifunctional monomer
copolymerizable with the alkyl (meth)acrylate, an emulsifier, and
water, the graft layer (g) being formed by grafting at least one
vinyl monomer selected from the group consisting of an aromatic
vinyl, an alkyl (meth)acrylate, and a vinyl cyanide to the rubbery
polymer (A-III), the alkyl (meth)acrylate including an alkyl
(meth)acrylate having 1 to 11 carbon atoms and an alkyl
(meth)acrylate having 12 to 30 carbon atoms.
24. The graft copolymer (B-III) according to claim 23, wherein the
amount of the alkyl (meth)acrylate having 12 to 30 carbon atoms is
0.1 to 50 parts by mass relative to 100 parts by mass of the total
amount of the alkyl (meth)acrylate having 1 to 11 carbon atoms and
the alkyl (meth)acrylate having 12 to 30 carbon atoms.
25. A graft copolymer (B-III) according to claim 23, wherein the
amount of the multifunctional monomer is 0.1 to 5.0 parts by mass
relative to 100 parts by mass of the total amount of the alkyl
(meth)acrylate and the multifunctional monomer.
26. The graft copolymer (B-III) according to claim 23, wherein the
graft layer (g) is produced by polymerizing the vinyl monomer with
the rubbery polymer (A-III) such that the proportion of the rubbery
polymer (A-III) is 10% to 90% by mass and the proportion of the
vinyl monomer is 90% to 10% by mass (with the total proportion of
the rubbery polymer (A-III) and the vinyl monomer being 100% by
mass).
27. The graft copolymer (B-III) according to claim 23, wherein the
rubbery polymer (A-III) included in the polymerization product of
the pre-emulsion has a volume-average particle size of less than
1000 nm.
28. A thermoplastic resin composition comprising the graft
copolymer (B-III) according to claim 23.
29. A molded article produced using the thermoplastic resin
composition according to claim 28.
30. A method for producing a rubbery polymer (A-III), the method
comprising a step in which a pre-emulsion is prepared using an
alkyl (meth)acrylate, a multifunctional monomer copolymerizable
with the alkyl (meth)acrylate, an emulsifier, and water, and a step
in which the emulsion is polymerized, the alkyl (meth)acrylate
including an alkyl (meth)acrylate having 1 to 11 carbon atoms and
an alkyl (meth)acrylate having 12 to 30 carbon atoms.
31. A method for producing a graft copolymer (B-III), the method
comprising grafting at least one vinyl monomer (b-III) selected
from the group consisting of an aromatic vinyl, an alkyl
(meth)acrylate, and a vinyl cyanide to a rubbery polymer (A-III)
produced by the method for producing a rubbery polymer (A-III)
according to claim 30 in order to form a graft layer (g).
32. A method for producing a thermoplastic resin composition, the
method comprising using a graft copolymer (B-III) produced by the
production method according to claim 31.
33. A method for producing a molded article, the method comprising
using a thermoplastic resin composition produced by the production
method according to claim 32.
Description
TECHNICAL FIELD
[0001] The present invention relates to the first to third
inventions below.
[0002] The first invention relates to a graft copolymer which has
good moldability and good continuous moldability and with which a
molded article having excellent impact resistance can be produced
and a method for producing the graft copolymer. The first invention
also relates to a method for producing a rubbery polymer with which
the above graft copolymer can be produced, a thermoplastic resin
composition including the graft copolymer, and a molded article
produced using the thermoplastic resin composition.
[0003] The second invention relates to a method for producing a
graft copolymer having excellent production stability and excellent
storage stability, a method for producing a thermoplastic resin
composition in which the graft copolymer is used, and a method for
producing a molded article in which the thermoplastic resin
composition is used.
[0004] The third invention relates to a graft copolymer which has
good moldability and with which a molded article having excellent
impact resistance and excellent appearance can be produced and a
method for producing the graft copolymer. The third invention also
relates to a method for producing a rubbery polymer with which the
above graft copolymer can be produced, a thermoplastic resin
composition including the graft copolymer, and a molded article
produced using the thermoplastic resin composition.
BACKGROUND ART
[0005] Thermoplastic resins have been used in various fields, such
as automobiles, housing and building materials, electrical and
electronic equipment, and OA instruments (e.g., printers). Among
the thermoplastic resins, an ABS resin and an ASA resin, which are
produced by mixing a styrene-acrylonitrile copolymer resin, an
.alpha.-methylstyrene-acrylonitrile copolymer resin, a
styrene-acrylonitrile-phenylmaleimide copolymer resin, or the like
with a graft copolymer prepared by grafting a monomer capable of
enhancing compatibility with the above resin to a rubbery polymer,
have been widely used because of their excellent impact resistance
and fluidity.
[0006] In particular, an ASA resin produced using constituents such
as an alkyl (meth)acrylate rubber, which is a saturated rubber, as
a rubbery polymer has good weather resistance but lower impact
resistance than an ABS resin. In order to enhance the impact
resistance of an ASA resin, there have been proposed an ASA resin
that includes an alkyl (meth)acrylate rubber having a specific
particle size (PTL 1) and an ASA resin that includes alkyl
(meth)acrylate rubbers having different particle sizes (PTL 2).
[0007] In PTL 1, large particles are formed by seed polymerization.
This results in an excessively long production time and poor
productivity. Furthermore, small acrylate rubber particles may also
be formed, which degrade moldability.
[0008] In PTL 2, large particles are formed by coagulation using an
acidic-group-containing copolymer latex. This results in excellent
productivity but an impact resistance lower than that of an
acrylate rubber having a uniform and large particle size.
Furthermore, it is necessary to increase the content of a rubbery
polymer in a thermoplastic resin composition for enhancing the
impact resistance of the ASA resin to a sufficiently high level.
Increasing the proportion of the rubbery polymer may degrade
moldability.
[0009] PTL 1: Japanese Patent 5805066
[0010] PTL 2: Japanese Patent Publication 2012-214734 A
SUMMARY OF INVENTION
[0011] An object of the first invention is to provide a graft
copolymer which has good moldability and good continuous
moldability and with which a thermoplastic resin molded article
having excellent impact resistance can be produced, a method for
producing the graft copolymer, a thermoplastic resin composition
including the graft copolymer, and a molded article produced using
the thermoplastic resin composition. Another object of the first
invention is to provide a method for producing a rubbery polymer
with which the above graft copolymer can be produced.
[0012] The inventors of the first invention found that the above
objects may be attained by a graft copolymer produced using a
rubbery polymer mixture including a rubbery polymer and a specific
hydrophobic substance, the rubbery polymer produced by polymerizing
an alkyl (meth)acrylate and a multifunctional monomer
copolymerizable with the alkyl (meth)acrylate.
[0013] The summary of the first invention is as follows.
[0014] [1] A graft copolymer (B-I) produced by grafting at least
one vinyl monomer (b-I) selected from the group consisting of an
aromatic vinyl, an alkyl (meth)acrylate, and a vinyl cyanide to a
rubbery polymer mixture including a rubbery polymer (A-I) and a
hydrophobic substance, the rubbery polymer (A-I) including an alkyl
(meth)acrylate unit and a multifunctional monomer unit
copolymerizable with an alkyl (meth)acrylate, the hydrophobic
substance having a kinematic viscosity of 5 mm.sup.2/s or more at
40.degree. C. or a kinematic viscosity of 2 to 4 mm.sup.2/s at
100.degree. C., a principal constituent of the hydrophobic
substance being a hydrocarbon.
[0015] [2] The graft copolymer (B-I) according to [1], wherein the
amount of the multifunctional monomer unit is 0.1 to 5.0 parts by
mass relative to 100 parts by mass of the total amount of the alkyl
(meth)acrylate unit and the multifunctional monomer unit.
[0016] [3] The graft copolymer (B-I) according to [1] or [2],
wherein the ratio between the rubbery polymer (A-I) and the vinyl
monomer (b-I) is such that the proportion of the rubbery polymer
(A-I) is 10% to 90% by mass and the proportion of the vinyl monomer
(b-I) is 90% to 10% by mass (with the total proportion of the
rubbery polymer (A-I) and the vinyl monomer (b-I) being 100% by
mass).
[0017] [4] The graft copolymer (B-I) according to any one of [1] to
[3], wherein the rubbery polymer mixture is a polymerization
product produced by polymerizing a miniemulsion containing the
alkyl (meth)acrylate, the multifunctional monomer, the hydrophobic
substance, an emulsifier, and water.
[0018] [5] The graft copolymer (B-I) according to [4], wherein the
amount of the hydrophobic substance is 0.1 to 10 parts by mass
relative to 100 parts by mass of the alkyl (meth)acrylate.
[0019] [6] The graft copolymer (B-I) according to [4] or [5],
wherein the rubbery polymer (A-I) included in the polymerization
product has a volume-average particle size of less than 1000
nm.
[0020] [7] A thermoplastic resin composition comprising the graft
copolymer (B-I) according to any one of [1] to [6].
[0021] [8] A molded article produced using the thermoplastic resin
composition according to [7].
[0022] [9] A method for producing a rubbery polymer (A-I), the
method comprising a miniemulsion formation step in which a mixture
(a-I) containing an alkyl (meth)acrylate, a multifunctional monomer
copolymerizable with the alkyl (meth)acrylate, a hydrophobic
substance, an emulsifier, and water is formed into a miniemulsion,
the hydrophobic substance having a kinematic viscosity of 5
mm.sup.2/s or more at 40.degree. C. or a kinematic viscosity of 2
to 4 mm.sup.2/s at 100.degree. C., a principal constituent of the
hydrophobic substance being a hydrocarbon, and a polymerization
step in which the miniemulsion is polymerized.
[0023] [10] A method for producing a graft copolymer (B-I), the
method comprising grafting at least one vinyl monomer (b-I)
selected from the group consisting of an aromatic vinyl, an alkyl
(meth)acrylate, and a vinyl cyanide to a rubbery polymer (A-I)
produced by the method for producing a rubbery polymer (A-I)
according to [9].
[0024] [11] A method for producing a thermoplastic resin
composition, the method comprising using a graft copolymer (B-I)
produced by the method for producing a graft copolymer (B-I)
according to [10].
[0025] [12] A method for producing a molded article, the method
comprising using a thermoplastic resin composition produced by the
method for producing a thermoplastic resin composition according to
[11].
[0026] An object of the second invention is to provide a method for
producing a graft copolymer having excellent production stability
and excellent storage stability; a thermoplastic resin composition
using the graft copolymer and being capable of producing a
thermoplastic resin molded article having excellent impact
resistance with good moldability; and a method for producing a
molded article of the thermoplastic resin composition.
[0027] The inventors of the second invention found that the above
objects may be attained by a graft copolymer produced using a
rubbery polymer prepared by polymerizing a pre-emulsion that is
formed using a mixture containing an alkyl (meth)acrylate, a
multifunctional monomer copolymerizable with the alkyl
(meth)acrylate, an oil-soluble initiator having a predetermined
number of carbon atoms, an emulsifier, and water.
[0028] The summary of the second invention is as follows.
[0029] [13] A method for producing a graft copolymer (B-II), the
method comprising a miniemulsion formation step in which a mixture
(a-II) containing an alkyl (meth)acrylate, a multifunctional
monomer copolymerizable with the alkyl (meth)acrylate, an
oil-soluble initiator having 16 or more carbon atoms, an
emulsifier, and water is formed into a miniemulsion, a
polymerization step in which the miniemulsion is polymerized to
form a rubbery polymer (A-II), and a graft polymerization step in
which at least one vinyl monomer (b-II) selected from the group
consisting of an aromatic vinyl, an alkyl (meth)acrylate, and a
vinyl cyanide is grafted to the rubbery polymer (A-II) in order to
produce a graft copolymer (B-II).
[0030] [14] The method for producing a graft copolymer (B-II)
according to [13], wherein the amount of the multifunctional
monomer is 0.1 to 5.0 parts by mass relative to 100 parts by mass
of the total amount of the alkyl (meth)acrylate and the
multifunctional monomer.
[0031] [15] The method for producing a graft copolymer (B-II)
according to [13] or [14], wherein the ratio between the rubbery
polymer (A-II) and the vinyl monomer (b-II) is such that the
proportion of the rubbery polymer (A-II) is 10% to 90% by mass and
the proportion of the vinyl monomer (b-II) is 90% to 10% by mass
(with the total proportion of the rubbery polymer (A-II) and the
vinyl monomer (b-II) being 100% by mass).
[0032] [16] The method for producing a graft copolymer (B-II)
according to any one of [13] to [15], wherein the amount of the
oil-soluble initiator used is 0.001 to 5 parts by mass relative to
100 parts by mass of the alkyl (meth)acrylate.
[0033] [17] The method for producing a graft copolymer (B-II)
according to any one of [13] to [16], wherein the amount of the
emulsifier used is 0.01 to 1.0 parts by mass relative to 100 parts
by mass of the alkyl (meth)acrylate.
[0034] [18] A method for producing a thermoplastic resin
composition, the method comprising using a graft copolymer (B-II)
produced by the production method according to any one of [13] to
[17].
[0035] [19] A method for producing a molded article, the method
comprising molding a thermoplastic resin composition produced by
the production method according to [18].
[0036] [20] A graft copolymer (B-II) produced by grafting at least
one vinyl monomer (b-II) selected from the group consisting of an
aromatic vinyl, an alkyl (meth)acrylate, and a vinyl cyanide to a
rubbery polymer (A-II) produced by miniemulsion polymerization of a
mixture (a-II) containing an alkyl (meth)acrylate, a
multifunctional monomer copolymerizable with the alkyl
(meth)acrylate, an oil-soluble initiator having 16 or more carbon
atoms, an emulsifier, and water.
[0037] [21] A thermoplastic resin composition comprising the graft
copolymer (B-II) according to [20].
[0038] [22] A molded article produced by molding the thermoplastic
resin composition according to [21].
[0039] An object of the third invention is to provide a graft
copolymer which has good moldability and with which a thermoplastic
resin molded article having excellent impact resistance and
excellent appearance can be produced, a method for producing the
graft copolymer, a thermoplastic resin composition including the
graft copolymer, and a molded article produced using the
thermoplastic resin composition. Another object of the third
invention is to provide a method for producing a rubbery polymer
with which the above graft copolymer can be produced.
[0040] The inventors of the third invention found that the above
objects may be attained by a graft copolymer that includes a
rubbery polymer and a graft layer, the rubbery polymer being
produced by polymerizing a pre-emulsion containing specific two
alkyl (meth)acrylates, a multifunctional monomer copolymerizable
with the alkyl (meth)acrylates, an emulsifier, and water.
[0041] The summary of the third invention is as follows.
[0042] [23] A graft copolymer (B-III) comprising a rubbery polymer
(A-III) and a graft layer (g), the rubbery polymer (A-III) being a
polymerization product produced by polymerizing a pre-emulsion
containing an alkyl (meth)acrylate, a multifunctional monomer
copolymerizable with the alkyl (meth)acrylate, an emulsifier, and
water, the graft layer (g) being formed by grafting at least one
vinyl monomer selected from the group consisting of an aromatic
vinyl, an alkyl (meth)acrylate, and a vinyl cyanide to the rubbery
polymer (A-III), the alkyl (meth)acrylate including an alkyl
(meth)acrylate having 1 to 11 carbon atoms and an alkyl
(meth)acrylate having 12 to 30 carbon atoms.
[0043] [24] The graft copolymer (B-III) according to [23], wherein
the amount of the alkyl (meth)acrylate having 12 to 30 carbon atoms
is 0.1 to 50 parts by mass relative to 100 parts by mass of the
total amount of the alkyl (meth)acrylate having 1 to 11 carbon
atoms and the alkyl (meth)acrylate having 12 to 30 carbon
atoms.
[0044] [25] A graft copolymer (B-III) according to [23] or [24],
wherein the amount of the multifunctional monomer is 0.1 to 5.0
parts by mass relative to 100 parts by mass of the total amount of
the alkyl (meth)acrylate and the multifunctional monomer.
[0045] [26] The graft copolymer (B-III) according to any one of
[23] to [25], wherein the graft layer (g) is produced by
polymerizing the vinyl monomer with the rubbery polymer (A-III)
such that the proportion of the rubbery polymer (A-III) is 10% to
90% by mass and the proportion of the vinyl monomer is 90% to 10%
by mass (with the total proportion of the rubbery polymer (A-III)
and the vinyl monomer being 100% by mass).
[0046] [27] The graft copolymer (B-III) according to any one of
[23] to [26], wherein the rubbery polymer (A-III) included in the
polymerization product of the pre-emulsion has a volume-average
particle size of less than 1000 nm.
[0047] [28] A thermoplastic resin composition comprising the graft
copolymer (B-III) according to any one of [23] to [27].
[0048] [29] A molded article produced using the thermoplastic resin
composition according to [28].
[0049] [30] A method for producing a rubbery polymer (A-III), the
method comprising a step in which a pre-emulsion is prepared using
an alkyl (meth)acrylate, a multifunctional monomer copolymerizable
with the alkyl (meth)acrylate, an emulsifier, and water, and a step
in which the emulsion is polymerized, the alkyl (meth)acrylate
including an alkyl (meth)acrylate having 1 to 11 carbon atoms and
an alkyl (meth)acrylate having 12 to 30 carbon atoms.
[0050] [31] A method for producing a graft copolymer (B-III), the
method comprising grafting at least one vinyl monomer (b-III)
selected from the group consisting of an aromatic vinyl, an alkyl
(meth)acrylate, and a vinyl cyanide to a rubbery polymer (A-III)
produced by the method for producing a rubbery polymer (A-III)
according to [30] in order to form a graft layer (g).
[0051] [32] A method for producing a thermoplastic resin
composition, the method comprising using a graft copolymer (B-III)
produced by the production method according to [31].
[0052] [33] A method for producing a molded article, the method
comprising using a thermoplastic resin composition produced by the
production method according to [32].
Advantageous Effects of Invention
[0053] The graft copolymer according to the first invention enables
the production of a thermoplastic resin composition having good
moldability and good continuous moldability and a molded article
having excellent impact resistance.
[0054] According to the second invention, a graft copolymer having
excellent production stability and excellent storage stability may
be produced. According to the second invention, a thermoplastic
resin composition having excellent moldability may be produced
using the graft copolymer. Furthermore, a molded article having
excellent impact resistance may be produced using the thermoplastic
resin composition.
[0055] The graft copolymer according to the third invention enables
the production of a thermoplastic resin composition having good
moldability and a molded article having excellent impact resistance
and excellent appearance.
BRIEF DESCRIPTION OF DRAWING
[0056] FIG. 1 is a schematic diagram illustrating a metal mold used
in a gas generation and deposition test in Examples.
DESCRIPTION OF EMBODIMENTS
[0057] Embodiments of the present invention are described in detail
below.
[0058] The term "unit" used herein refers to a structural portion
originating from a monomer before polymerization. For example, the
term "alkyl (meth)acrylate unit" refers to "structural portion
originating from alkyl (meth)acrylate".
[0059] The term "(meth)acrylate" used herein refers to one or both
of "acrylate" and "methacrylate".
[0060] The term "principal constituent" used herein refers to a
constituent the proportion of which is 50% by mass or more, is
preferably 70% by mass or more, and is more preferably 90% to 100%
by mass.
[0061] The term "molded article" used herein refers to an article
produced by molding a thermoplastic resin composition.
Embodiment of First Invention
[0062] A graft copolymer (B-I) according to the first invention is
produced by grafting at least one vinyl monomer (b-I) selected from
the group consisting of an aromatic vinyl, an alkyl (meth)acrylate,
and a vinyl cyanide to a rubbery polymer mixture including a
rubbery polymer (A-I) and a hydrophobic substance, the rubbery
polymer (A-I) including an alkyl (meth)acrylate unit and a
multifunctional monomer unit copolymerizable with the alkyl
(meth)acrylate (hereinafter, this multifunctional monomer may be
referred to simply as "multifunctional monomer"), the hydrophobic
substance having a kinematic viscosity of 5 mm.sup.2/s or more at
40.degree. C. or a kinematic viscosity of 2 to 4 mm.sup.2/s at
100.degree. C., a principal constituent of the hydrophobic
substance being a hydrocarbon (hereinafter, this hydrophobic
substance may be referred to simply as "hydrophobic
substance").
[0063] [Rubbery Polymer (A-I)]
[0064] The rubbery polymer (A-I) (hereinafter, may be referred to
as "rubbery polymer (A-I) according to the first invention")
included in the rubbery copolymer mixture according to the first
invention is described below.
[0065] The rubbery polymer (A-I) according to the first invention
is produced in the form of a mixture containing the rubbery polymer
(A-I) and a hydrophobic substance, the mixture being produced by
polymerizing a miniemulsion prepared preferably using a mixture of
an alkyl (meth)acrylate, a multifunctional monomer, a hydrophobic
substance, and an emulsifier and more preferably using a mixture of
an alkyl (meth)acrylate, a multifunctional monomer, a hydrophobic
substance, an emulsifier, and water.
[0066] A method for producing the rubbery polymer (A-I) according
to the first invention by miniemulsion polymerization, that is, by
polymerizing a miniemulsion prepared using a mixture of an alkyl
(meth)acrylate, a multifunctional monomer, a hydrophobic substance,
an emulsifier, and water, is described below.
[0067] <Mechanisms of Miniemulsion>
[0068] In miniemulsion polymerization, monomer oil droplets having
a size of about 100 to 1000 nm are prepared by applying a large
shearing force to the mixture with an ultrasonic generator or the
like. In this process, the molecules of the emulsifier adsorb
preferentially onto the surfaces of the monomer oil droplets and,
consequently, free emulsifier molecules and micelles are
substantially not contained in the aqueous medium. Thus, in ideal
miniemulsion polymerization, monomer radicals are not distributed
to a water phase and an oil phase, but the monomer oil droplets
serve as nuclei of particles whereby the polymerization proceeds.
Consequently, the monomer oil droplets are converted directly into
polymer particles. This enables the production of homogeneous
polymer nanoparticles. The graft copolymer (B-I) produced using the
nanoparticles of the rubbery polymer (A-I) prepared in the
above-described manner enables impact resistance to be improved to
a sufficient level.
[0069] In contrast, in the case where polymer particles are
prepared by common emulsion polymerization, the monomer oil
droplets are converted into micelles during the reaction.
Therefore, when a plurality of monomers having different degrees of
hydrophobicity are used, the likelihood of monomer oil droplets
being converted into micelles varies by monomer and, consequently,
it becomes not possible to form homogeneous polymer.
[0070] <Miniemulsion Polymerization>
[0071] Examples of miniemulsion polymerization used for producing
the rubbery polymer (A-I) according to the first invention include,
but are not limited to, a method including the following steps:
mixing monomers including at least an alkyl (meth)acrylate and a
multifunctional monomer with an emulsifier, a hydrophobic
substance, and, preferably, a radical polymerization initiator;
applying a shearing force to the resulting mixture (hereinafter,
may be referred to as "mixture (a-I)") in order to prepare a
pre-emulsion; and heating the emulsion to a polymerization
initiation temperature in order to polymerize the emulsion.
[0072] In miniemulsion polymerization, after the polymerizable
monomers have been mixed with the emulsifier, a shearing process is
performed using ultrasonic irradiation or the like. This causes the
monomers to be torn by the shearing force and forms monomer oil
microdroplets covered with the emulsifier. The monomer oil
microdroplets are subsequently heated to the polymerization
initiation temperature of the radical polymerization initiator to
be directly polymerized. Hereby, high-molecular microparticles are
formed. For applying the shearing force to the mixture in the
preparation of the miniemulsion, any publicly known method may be
used.
[0073] A high-shear apparatus that can be used for preparing the
miniemulsion is not limited to the above apparatus; for example, an
emulsification apparatus that includes a high-pressure pump and an
interaction chamber and an apparatus that forms a miniemulsion by
using ultrasonic energy or a high-frequency wave may be used.
Examples of the emulsification apparatus that includes a
high-pressure pump and an interaction chamber include
"Microfluidizer" produced by Powrex Corporation. Examples of the
apparatus that forms a miniemulsion by using ultrasonic energy or a
high-frequency wave include "Sonic Dismembrator" produced by Fisher
Scient and "ULTRASONIC HOMOGENIZER" produced by NIHONSEIKI KAISHA
LTD.
[0074] The amount of the water solvent used for preparing the
miniemulsion is preferably about 100 to 500 parts by mass relative
to 100 parts by mass of the mixture (a-I) excluding water in order
to set the solid component concentration in the reaction system
after polymerization to about 5% to 50% by mass in consideration of
workability, stability, productivity, and the like.
[0075] <Alkyl (Meth)Acrylate>
[0076] Examples of the alkyl (meth)acrylate constituting the
rubbery polymer (A-I) according to the first invention include
alkyl acrylates including an alkyl group having 1 to 22 carbon
atoms, such as methyl acrylate, ethyl acrylate, n-propyl acrylate,
n-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, and
stearyl acrylate; and alkyl methacrylates including an alkyl group
having 1 to 22 carbon atoms, such as hexyl methacrylate,
2-ethylhexyl methacrylate, n-dodecyl methacrylate, lauryl
methacrylate, and stearyl methacrylate. Among the above alkyl
(meth)acrylates, n-butyl acrylate is preferable because it enhances
the impact resistance and glossiness of a molded article produced
using the thermoplastic resin composition. The above alkyl
(meth)acrylates may be used alone or in combination of two or
more.
[0077] <Multifunctional Monomer>
[0078] In the production of the rubbery polymer (A-I) according to
the first invention, a multifunctional monomer is used in
combination with the alkyl (meth)acrylate in order to introduce a
crosslinked structure to the poly(alkyl (meth)acrylate) component
originating from the alkyl (meth)acrylate. The crosslinking
portions of the crosslinked rubbery polymer (A-I) produced using a
multifunctional monomer also serve as a graft junction at which the
vinyl monomer (b-I) described below is grafted to the rubbery
polymer (A-I) in the production of the graft copolymer (B-I)
according to the first invention.
[0079] Examples of the multifunctional monomer include allyl
(meth)acrylate, butylene di(meth)acrylate, ethylene glycol
di(meth)acrylate, propylene glycol di(meth)acrylate, 1,3-butylene
glycol di(meth)acrylate, 1,4-butylene glycol di(meth)acrylate,
triallyl cyanurate, and triallyl isocyanurate. The above
multifunctional monomers may be used lone or in combination of two
or more.
[0080] The amount of the multifunctional monomer used is
preferably, but not limited to, 0.1 to 5.0 parts by mass relative
to 100 parts by mass of the total amount of the multifunctional
monomer and the alkyl (meth)acrylate.
[0081] The amount of multifunctional monomer unit included in the
rubbery polymer (A-I) according to the first invention is
preferably 0.1 to 5.0 parts by mass relative to 100 parts by mass
of the total amount of the multifunctional monomer unit and the
alkyl (meth)acrylate unit.
[0082] If the proportion of the multifunctional monomer used is
lower than the above lower limit, a sufficient crosslinked
structure may fail to be formed by using the multifunctional
monomer in combination with the alkyl (meth)acrylate and,
consequently, impact resistance may fail to be enhanced. If the
proportion of the multifunctional monomer used is higher than the
above upper limit, the properties of a rubber may fail to be
achieved as a result of excessive crosslinking and, consequently,
impact resistance may become degraded.
[0083] <Hydrophobic Substance>
[0084] Addition of a hydrophobic substance in the formation of the
miniemulsion is likely to further enhance stability. Using a
hydrophobic substance also limits an increase in variation in
particle size which results from Ostwald ripening and enables the
synthesis of a monodisperse latex particles.
[0085] Examples of the hydrophobic substance include
nonpolymerizable hydrophobic compounds. Examples thereof include
hydrocarbons having 10 or more carbon atoms, alcohols having 10 or
more carbon atoms, hydrophobic polymers having a mass-average
molecular weight (Mw) of less than 10000, hydrophobic monomers,
such as a vinyl ester of an alcohol having 10 to 30 carbon atoms, a
vinyl ether of an alcohol having 12 to 30 carbon atoms, a vinyl
ester of a carboxylic acid having 10 to 30 carbon atoms (preferably
10 to 22 carbon atoms), and p-alkylstyrene, hydrophobic
chain-transfer agents, and hydrophobic peroxides. The above
hydrophobic substances may be used alone or in a mixture of two or
more.
[0086] In the first invention, among the above hydrophobic
substances, hydrophobic substances having a kinematic viscosity of
5 mm.sup.2/s or more, preferably 20 mm.sup.2/s or more, and further
preferably 30 mm.sup.2/s or more at 40.degree. C. are used when the
hydrophobic substances are liquid at room temperature, and
hydrophobic substances having a kinematic viscosity of 2 to 4
mm.sup.2/s and preferably 2.5 to 3.5 mm.sup.2/s at 100.degree. C.
are used when the hydrophobic substances are solid at room
temperature. Using a hydrophobic substance having a kinematic
viscosity that falls within the above range reduces the amount of
gas generated during molding, accordingly enhances continuous
moldability, and is desirable in terms of impact resistance.
[0087] In the first invention, the kinematic viscosity of the
hydrophobic substance is measured in accordance with ASTM-D445.
[0088] Specific examples of the hydrophobic substance include
liquid paraffin, liquid isoparaffin, a paraffin wax, a polyethylene
wax, an olive oil, and a polystyrene, a poly (meth)acrylate, and a
polybutylene glycol that have a mass-average molecular weight (Mw)
of 500 to 10000.
[0089] The amount of the hydrophobic substance used is preferably
0.1 to 10 parts by mass and is further preferably 1 to 3 parts by
mass relative to 100 parts by mass of the alkyl (meth)acrylate. If
the amount of the hydrophobic substance used is smaller than the
above lower limit, the impact resistance of the graft copolymer
(B-I) fails to be enhanced by a sufficient degree. If the amount of
the hydrophobic substance used is larger than the above upper
limit, a large amount of gas may be deposited on the metal mold
during molding, which degrades continuous moldability.
[0090] <Emulsifier>
[0091] Examples of the emulsifier used for producing the rubbery
polymer (A-I) include the following publicly known emulsifiers:
carboxylic acid emulsifiers, such as alkali metal salts of oleic
acid, palmitic acid, stearic acid, and rosin acid and alkali metal
salts of alkenylsuccinic acid; and anionic emulsifiers, such as an
alkyl sulfuric acid ester, sodium alkylbenzene sulfonate, sodium
alkyl sulfosuccinate, and polyoxyethylene nonylphenyl ether sulfate
ester sodium. The above emulsifiers may be used alone or in
combination of two or more.
[0092] The amount of the emulsifier used is preferably 0.01 to 1.0
parts by mass and is further preferably 0.05 to 0.5 parts by mass
relative to 100 parts by mass of the alkyl (meth)acrylate.
[0093] <Radical Polymerization Initiator>
[0094] As a radical polymerization initiator used in the
polymerization step subsequent to the miniemulsification step, a
known one can be used. Examples of radical polymerization
initiators include azo polymerization initiators,
photopolymerization initiators, inorganic peroxides, organic
peroxides, and redox initiators containing organic peroxides,
transition metals, and reducing agents in combination. Of these,
azo polymerization initiators, inorganic peroxides, organic
peroxides, and redox initiators, which are capable of initiating
polymerization upon heating, are preferred. The radical initiators
may be used alone or in a combination of two or more.
[0095] Examples of azo polymerization initiators include
2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile),
2,2'-azobis(2,4-dimethylvaleronitrile),
2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile),
1,1'-azobis(cyclohexane-1-carbonitrile),
1-[(1-cyano-1-methylethyl)azo]formamide, 4,4'-azobis(4-cyanovaleric
acid), dimethyl 2,2'-azobis(2-methyl propionate), dimethyl
1,1'-azobis(1-cychexanecarboxylate),
2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide],
2,2'-azobis(N-butyl-2-methylpropionamide),
2,2'-azobis(N-cyclohexyl-2-methylpropionamide),
2,2'-azobis[2-(2-imidazolin-2-yl)propane], and
2,2'-azobis(2,4,4-trimethylpentane).
[0096] Examples of inorganic peroxides include potassium
persulfate, sodium persulfate, ammonium persulfate, and hydrogen
peroxide.
[0097] Examples of organic peroxides include peroxyester compounds.
Specific examples thereof include
.alpha.,.alpha.'-bis(neodecanoylperoxy)diisopropylbenzene, cumyl
peroxyneodecanoate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate,
1-cyclohexyl-1-methylethyl peroxyneodecanoate, t-hexyl
peroxyneodecanoate, t-butyl peroxyneodecanoate, t-hexyl
peroxypivalate, t-butyl peroxypivalate, 1,1,3,3-tetramethylbutyl
peroxy-2-ethylhexanoate, di(3,3,5-trimethylhexanoyl) peroxide,
2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane,
1-cyclohexyl-1-methylethyl peroxy-2-ethylhexanoate, t-hexyl
peroxy-2-hexylhexanoate, t-butyl peroxy-2-hexylhexanoate, t-butyl
peroxyisobutyrate, t-hexyl peroxyisopropylmonocarbonate, t-butyl
peroxymaleic acid, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl
peroxylaurate, 2,5-dimethyl-2,5-bis(m-toluoylperoxy)hexane, t-butyl
peroxyisopropylmonocarbonate, t-butyl
peroxy-2-ethylhexylmonocarbonate, t-hexyl peroxybenzoate,
2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, t-butyl peroxyacetate,
t-butyl peroxy-m-toluoylbenzoate, t-butyl peroxybenzoate,
bis(t-butylperoxy) isophthalate,
1,1-bis(t-hexylperoxy)3,3,5-trimethylcyclohexane,
1,1-bis(t-hexylperoxy)cyclohexane,
1,1-bis(t-butylperoxy)3,3,5-trimethylcyclohexane,
1,1-bis(t-butylperoxy)cyclohexane,
1,1-bis(t-butylperoxy)cyclododecane, 2,2-bis(t-butylperoxy)butane,
n-butyl 4,4-bis(t-butylperoxy)valerate,
2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane,
.alpha.,.alpha.'-bis(t-butylperoxide)diisopropylbenzene, dicumyl
peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, t-butyl cumyl
peroxide, di-t-butylperoxide, cumene hydroperoxide,
diisopropylbenzene hydroperoxide, dilauroyl peroxide, diisononanoyl
peroxide, bis(4-t-butylcyclohexyl) peroxydicarbonate, t-butyl
hydroperoxide, benzoyl peroxide, lauroyl peroxide,
dimethylbis(t-butylperoxy)hexyne-3,
bis(t-butylperoxyisopropyl)benzene,
bis(t-butylperoxy)trimethylcyclohexane,
2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane,
butyl-bis(t-butylperoxy) valerate, t-butyl peroxy-2-ethylhexanoate,
dibenzoyl peroxide, paramenthane hydroperoxide, and t-butyl
peroxybenzoate.
[0098] As a redox initiator, a combination of an organic peroxide,
ferrous sulfate, a chelating agent, and a reducing agent is
preferred. Examples include a combination of cumene hydroperoxide,
ferrous sulfate, sodium pyrophosphate, and dextrose and a
combination of t-butyl hydroperoxide, sodium formaldehyde
sulfoxylate (Rongalite), ferrous sulfate, and disodium
ethylenediaminetetraacetate.
[0099] The addition amount of radical initiator is typically 5
parts by mass or less, preferably 3 parts by mass or less, for
example 0.001 to 3 parts by mass, relative to 100 parts by mass of
the alkyl (meth)acrylate.
[0100] The radical polymerization initiator may be added before or
after the miniemulsion is formed and may be added in one portion,
in multiple portions, or in a continuous manner.
[0101] <Rubber Component>
[0102] A rubbery polymer (A-I) that is a rubber composite may be
produced by adding another rubber component to the mixture (a-I) in
the production of the rubbery polymer (A-I) according to the first
invention such that the desired properties are not impaired.
Examples of the other rubber component include diene rubbers, such
as polybutadiene, and polyorganosiloxane. Polymerizing the alkyl
(meth)acrylate in the presence of the above rubber components
produces a rubbery polymer (A-I) that is a diene/alkyl
(meth)acrylate rubber composite or a polyorganosiloxysane/alkyl
(meth)acrylate rubber composite, which contains an alkyl
(meth)acrylate rubber, such as a butyl acrylate rubber. The rubber
composite according to the first invention is not limited to the
above rubber composites. The rubber components that can be included
in the rubber composite may be used alone or in combination of two
or more.
[0103] <Reaction Conditions>
[0104] The miniemulsion formation step is conducted normally at
room temperature (about 10.degree. C. to 50.degree. C.). The
polymerization step subsequent to the miniemulsion formation step
is conducted normally at 40.degree. C. to 100.degree. C. for about
30 to 600 minutes.
[0105] <Particle Size>
[0106] The volume-average particle size of the rubbery polymer
(A-I) according to the first invention which can be produced by the
miniemulsion polymerization described above is preferably 1000 nm
or less, that is, for example, 100 to 600 nm, in consideration of
polymerization stability. The volume-average particle size of the
rubbery polymer (A-I) is measured by the method described in
Examples below.
[0107] [Graft Copolymer (B-I)]
[0108] The graft copolymer (B-I) according to the first invention
is produced by grafting at least one vinyl monomer (b-I) selected
from an aromatic vinyl, an acryl (meth)acrylate, and a vinyl
cyanide to a rubbery polymer mixture (hereinafter, may be referred
to as "latex") that includes the rubbery polymer (A-I) according to
the first invention, which is produced in the above-described
manner, and the hydrophobic substance.
[0109] The graft copolymer (B-I) according to the first invention
may further include a vinyl monomer other than an aromatic vinyl,
an alkyl (meth)acrylate, or a vinyl cyanide which is grafted
thereto.
[0110] Using a mixture of an aromatic vinyl, which is preferably
styrene, with a vinyl cyanide, which is preferably acrylonitrile,
as a vinyl monomer (b-I), advantageously enhances the thermal
stability of the graft copolymer (B-I). In such a case, the ratio
between the amounts of the aromatic vinyl, such as styrene, and the
vinyl cyanide, such as acrylonitrile, is preferably set such that
the amount of aromatic vinyl is 50% to 90% by mass relative to 10%
to 50% by mass of vinyl cyanide (with the total amount of aromatic
vinyl and vinyl cyanide being 100% by mass).
[0111] The graft copolymer (B-I) is preferably an emulsion graft
copolymer produced by grafting 90% to 10% by mass vinyl monomer
(b-I) to 10% to 90% by mass rubbery polymer (A-I) in order to
enhance the appearance of the molded article (with the total amount
of the rubbery polymer (A-I) and the vinyl monomer (b-I) being 100
mass %). The above ratio is further preferably set such that the
proportion of the rubbery polymer (A-I) is 30% to 70% by mass and
the proportion of the vinyl monomer (b-I) is 70% to 30% by
mass.
[0112] For grafting the vinyl monomer (b-I) to the rubbery polymer
(A-I), for example, the vinyl monomer (b-I) is added to the latex
containing the rubbery polymer (A-I) produced by miniemulsion
polymerization and, subsequently, polymerization is performed in a
single stage or multiple stages. In the case where polymerization
is performed in multiple stages, it is preferable to perform
polymerization while adding the vinyl monomer (b-I) in batches or
continuously in the presence of the rubber latex containing the
rubbery polymer (A-I). The above polymerization method achieves
good polymerization stability and enables a latex having a desired
particle size and a desired particle size distribution to be
produced with consistency.
[0113] Examples of a polymerization initiator used for performing
the graft polymerization are the same as the examples of the
radical polymerization initiator used for performing the
miniemulsion polymerization of the alkyl (meth)acrylate described
above.
[0114] When the rubbery polymer (A-I) is polymerized with the vinyl
monomer (b-I), an emulsifier may be used in order to stabilize the
latex and control the average particle size of the graft copolymer
(B-I). Examples of the emulsifier are not limited and may be the
same as the examples of the emulsifier used in the miniemulsion
polymerization of the alkyl (meth)acrylate described above. An
anionic emulsifier and a nonionic emulsifier are preferable. The
amount of the emulsifier used for grafting the vinyl monomer (b-I)
to the rubbery polymer (A-I) is preferably, but not limited to, 0.1
to 10 parts by mass and is more preferably 0.2 to 5 parts by mass
relative to 100 parts by mass of the graft copolymer (B-I).
[0115] A method for recovering the graft copolymer (B-I) from the
latex containing the graft copolymer (B-I) which is produced by
emulsion polymerization is not limited; for example, the following
method may be used.
[0116] The latex containing the graft copolymer (B-I) is charged
into hot water containing a coagulant dissolved therein in order to
solidify the graft copolymer (B-I). The solidified graft copolymer
(B-I) is re-dispersed in water or warm water to form a slurry in
order to elute the residue of the emulsifier remaining in the graft
copolymer (B-I) into water, thereby the graft copolymer (B-I) is
cleaned. The slurry is then dehydrated with a dehydrator or the
like. The resulting solid is dried with a flash dryer or the like.
Hereby, the graft copolymer (B-I) is recovered in the form of a
powder or particles.
[0117] Examples of the coagulant include inorganic acids (e.g.,
sulfuric acid, hydrochloric acid, phosphoric acid, and nitric acid)
and metal salts (e.g., calcium chloride, calcium acetate, and
aluminum sulfate). The coagulant is selected appropriately in
accordance with the type of the emulsifier used. For example, any
coagulant may be used in the case where the emulsifier used is only
a carboxylic acid salt (e.g., a fatty acid salt or rosin acid
soap). In the case where the emulsifier used is an emulsifier
having a stable emulsifying capacity even in an acidic region, such
as sodium alkylbenzene sulfonate, using an inorganic acid as a
coagulant may be insufficient; a metal salt needs to be used as a
coagulant.
[0118] The volume-average particle size of the graft copolymer
(B-I) according to the first invention, which is produced using the
rubbery polymer (A-I) according to the first invention in the
above-described manner, is normally less than 1000 nm. The average
particle size of the graft copolymer (B-I) is measured by the
method described in Examples below.
[0119] [Thermoplastic Resin Composition]
[0120] The thermoplastic resin composition according to the first
invention includes the graft copolymer (B-I) according to the first
invention described above. The amount of graft copolymer (B-I) is
preferably 20 to 60 parts by mass relative to 100 parts by mass of
the thermoplastic resin composition. If the content of the graft
copolymer (B-I) in the thermoplastic resin composition is less than
20 parts by mass, the amount of rubber is small and the impact
resistance of the molded article may become degraded accordingly.
If the content of the graft copolymer (B-I) in the thermoplastic
resin composition is more than 60 parts by mass, the thermoplastic
resin composition may have poor fluidity.
[0121] The amount of graft copolymer (B-I) is more preferably 30 to
40 parts by mass relative to 100 parts by mass of the thermoplastic
resin composition according to the first invention in order to
achieve a certain degree of fluidity, a certain degree of impact
resistance of the molded article, and certain degrees of other
physical properties in a balanced manner.
[0122] The thermoplastic resin composition according to the first
invention may optionally include other thermoplastic resins and
additives.
[0123] Examples of the other thermoplastic resins include polyvinyl
chloride, polystyrene, an acrylonitrile-styrene copolymer, a
styrene-acrylonitrile-N-phenylmaleimide copolymer, an
.alpha.-methylstyrene-acrylonitrile copolymer, poly(methyl
methacrylate), a methyl methacrylate-styrene copolymer,
polycarbonate, polyamide, a polyester, such as polyethylene
terephthalate or polybutylene terephthalate, and a polyphenylene
ether-polystyrene blend. The above thermoplastic resins may be used
alone or in combination of two or more. Among the above
thermoplastic resins, an acrylonitrile-styrene copolymer is
preferable in consideration of impact resistance and fluidity.
[0124] Examples of the additives include a colorant, such as a
pigment or a dye, a filler (e.g., carbon black, silica, or titanium
oxide), a flame retardant, a stabilizer, a reinforcing agent, a
processing aid, a heat-resistant agent, an antioxidant, a
weathering agent, a mold release agent, a plasticizer, and an
antistatic agent.
[0125] The thermoplastic resin composition according to the first
invention is produced by mixing the graft copolymer (B-I) with the
optional thermoplastic resins and additives using a V-blender, a
Henschel mixer, or the like and melt-kneading the resulting mixture
with a kneader, such as an extruder, a Banbury mixer, a pressure
kneader, or a roller.
[0126] The order in which the above constituents are mixed is not
limited; the above constituents may be mixed in any order as long
as all the constituents are uniformly mixed.
[0127] [Molded Article]
[0128] The molded article according to the first invention is
produced by molding the thermoplastic resin composition according
to the first invention and has excellent impact resistance.
[0129] For molding the thermoplastic resin composition according to
the first invention, for example, injection molding, an injection
compression molding machine method, extrusion, blow molding, vacuum
molding, compressed air molding, calender molding, and inflation
molding may be used. Among the above molding methods, injection
molding and injection compression molding are preferable because
they enable excellent mass productivity and the production of a
molded article with high dimensional accuracy.
[0130] The molded article according to the first invention, which
is produced by molding the thermoplastic resin composition
according to the first invention, has excellent impact resistance
and is suitably used as an automotive interior or exterior
component, an OA instrument, a building material, or the like.
[0131] The molded article according to the first invention, which
is produced by molding the thermoplastic resin composition
according to the first invention, may be used in the following
industrial applications: automotive components and, in particular,
paintless interior and exterior components; building materials,
such as a wall material and a window frame; tableware; toys;
electric home appliances, such as a cleaner housing, a television
housing, and an air-conditioner housing; interior materials; ship
materials; and telecommunication equipment housings.
Embodiment of Second Invention
[0132] A method for producing the graft copolymer (B-II) according
to the second invention includes a miniemulsion formation step in
which a mixture (a-II) containing an alkyl (meth)acrylate, a
multifunctional monomer copolymerizable with the alkyl
(meth)acrylate (hereinafter, this multifunctional monomer may be
referred to simply as "multifunctional monomer"), an oil-soluble
initiator having 16 or more carbon atoms (hereinafter, this
oil-soluble initiator may be referred to simply as "oil-soluble
initiator"), an emulsifier, and water is formed into a
miniemulsion, a polymerization step in which the miniemulsion is
polymerized to form a rubbery polymer (A-II) (hereinafter, may be
referred to as "rubbery polymer (A-II) according to the second
invention"), and a graft polymerization step in which at least one
vinyl monomer (b-II) selected from the group consisting of an
aromatic vinyl, an alkyl (meth)acrylate, and a vinyl cyanide is
grafted to the rubbery polymer (A-II) in order to produce the graft
copolymer (B-II) (hereinafter, may be referred to as "graft
copolymer (B-II) according to the second invention").
[0133] [Rubbery Polymer (A-II)]
[0134] A method for producing the rubbery polymer (A-II) according
to the second invention is described below.
[0135] The rubbery polymer (A-II) according to the second invention
is produced by conducting a miniemulsion formation step in which a
mixture containing an alkyl (meth)acrylate, a multifunctional
monomer, an oil-soluble initiator, an emulsifier, and water is
formed into a miniemulsion by miniemulsion polymerization and a
polymerization step in which the emulsion is polymerized.
[0136] The mechanisms of miniemulsion and miniemulsion
polymerization are as described in the sections "Mechanisms of
Miniemulsion" and "Miniemulsion Polymerization" in the first
invention. The descriptions in the above sections directly apply to
the second invention except that the terms "rubbery polymer (A-I)",
"mixture (a-I)", and "graft copolymer (B-I)" are read as "rubbery
polymer (A-II)", "mixture (a-II)", and "graft copolymer (B-II)",
respectively. Note that, in the second invention, an oil-soluble
initiator is used as a radical polymerization initiator.
[0137] The miniemulsion polymerization performed for producing the
rubbery polymer (A-II) according to the second invention includes a
step in which monomers including at least an alkyl (meth)acrylate
and a multifunctional monomer, an oil-soluble initiator, and an
emulsifier are mixed with water, a step in which the mixture
(hereinafter, may be referred to as "mixture (a-II)") is formed
into a pre-emulsion by the application of a shearing force, and a
step in which the emulsion is heated to a polymerization initiation
temperature to be polymerized.
[0138] The amount of the water solvent used in the preparation of
the pre-emulsion is also the same as in the first invention
described above.
[0139] <Alkyl (Meth)Acrylate>
[0140] Examples of the alkyl (meth)acrylate constituting the
rubbery polymer (A-II) according to the second invention are the
same as the examples of the alkyl (meth)acrylate constituting the
rubbery polymer (A-I) according to the first invention. The alkyl
(meth)acrylates may be used alone or in combination of two or more.
Preferable examples of the alkyl (meth)acrylate are also the same
as those of the alkyl (meth)acrylate constituting the rubbery
polymer (A-I).
[0141] <Multifunctional Monomer>
[0142] The descriptions of the function, specific examples, amount,
and the like of the multifunctional monomer used for producing the
rubbery polymer (A-I) according to the first invention directly
apply to the multifunctional monomer used for producing the rubbery
polymer (A-II) according to the second invention.
[0143] <Oil-Soluble Initiator>
[0144] The oil-soluble initiator is a radical polymerization
initiator soluble in oils, that is, soluble in the alkyl
(meth)acrylate and the multifunctional monomer. In the second
invention, at least a compound that has 16 or more carbon atoms,
preferably 20 or more carbon atoms, and further preferably 22 or
more carbon atoms is used as an oil-soluble initiator. Examples of
the oil-soluble initiator include an azo polymerization initiator,
a photopolymerization initiator, an organic peroxide, and a redox
initiator that includes an organic peroxide, a transition metal,
and a reductant. Among the above initiators, an azo polymerization
initiator and an organic peroxide, with which polymerization can be
initiated by heat, are preferable. The above initiators may be used
alone or in combination of two or more.
[0145] In the second invention, an oil-soluble initiator that has a
certain number or more of carbon atoms is used. This enhances the
stability of the latex that has been subjected to the miniemulsion
formation step and, accordingly, production stability during the
polymerization step and storage stability subsequent to the
polymerization step. This also limits an increase in variation in
particle size which results from Ostwald ripening and enables the
synthesis of a monodisperse latex particles.
[0146] In contrast, if an oil-soluble initiator having less than 16
carbon atoms is used, the stability of the pre-emulsion is poor, a
large amount of coagulum may be formed in the polymerization step,
and, consequently, the storage stability of the latex that has been
subjected to the graft polymerization described below may become
degraded. The upper limit for the number of carbon atoms included
in the oil-soluble initiator is not limited but normally 31 or
less.
[0147] Examples of the azo polymerization initiator include
dimethyl 1,1'-azobis(1-cyclohexanecarboxylate),
2,2'-azobis(N-butyl-2-methylpropionamide),
2,2'-azobis(N-cyclohexyl-2-methylpropionamide), and
2,2'-azobis(2,4,4-trimethylpentane).
[0148] Examples of the organic peroxide include peroxy esters.
Specific examples thereof include
.alpha.,.alpha.'-bis(neodecanoylperoxy)diisopropylbenzene, cumyl
peroxyneodecanoate, t-hexyl peroxyneodecanoate,
1,1,3,3-tetramethylbutyl peroxyneodecanoate,
1-cyclohexyl-1-methylethyl peroxyneodecanoate,
1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate,
di(3,3,5-trimethylhexanoyl) peroxide,
2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane,
1-cyclohexyl-1-methylethyl peroxy-2-ethylhexanoate, t-hexyl peroxy
2-hexyl hexanoate, bis(4-t-butylcyclohexyl) peroxydicarbonate,
2,5-dimethyl-2,5-bis(m-toluoylperoxy)hexane,
2,5-dimethyl-2,5-bis(benzoylperoxy)hexane,
1,1-bis(t-hexylperoxy)3,3,5-trimethyl cyclohexane,
1,1-bis(t-hexylperoxy) cyclohexane,
1,1-bis(t-butylperoxy)3,3,5-trimethylcyclohexane,
1,1-bis(t-butylperoxy)cyclododecane,
n-butyl-4,4-bis(t-butylperoxy)valerate,
2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane,
.alpha.,.alpha.'-bis(t-butylperoxy)diisopropylbenzene, dilauroyl
peroxide, diisononanoyl peroxide, dicumyl peroxide,
2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane,
2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, dimethyl
bis(t-butylperoxy)-3-hexyne,
1,4-bis(t-butylperoxyisopropyl)benzene,
1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, and butyl
4,4-bis(t-butylperoxy)valerate.
[0149] The amount of the oil-soluble initiator used is 0.001 to 5
parts by mass and is preferably 0.1 to 3 parts by mass relative to
100 parts by mass of the alkyl (meth)acrylate.
[0150] <Emulsifier>
[0151] The descriptions of the specific examples, amount, and the
like of the emulsifier used for producing the rubbery polymer (A-I)
according to the first invention directly apply to the emulsifier
used for producing the rubbery polymer (A-II) according to the
second invention.
[0152] <Hydrophobic Substance>
[0153] A hydrophobic substance may be used in the production of the
rubbery polymer (A-II) according to the second invention in an
amount at which the desired properties of the second invention are
not impaired. Using a hydrophobic substance in the formation of the
pre-emulsion may further enhance the stability with which the
miniemulsion polymerization is performed.
[0154] Examples of the hydrophobic substance include
nonpolymerizable hydrophobic compounds, such as hydrocarbons having
10 or more carbon atoms and alcohols having 10 or more carbon
atoms; hydrophobic polymers having a mass-average molecular weight
(Mw) of less than 10000; hydrophobic monomers, such as a vinyl
ester of an alcohol having 10 to 30 carbon atoms, a vinyl ether of
an alcohol having 12 to 30 carbon atoms, a vinyl ester of a
carboxylic acid having 10 to 30 carbon atoms (preferably 10 to 22
carbon atoms), and p-alkylstyrene; and hydrophobic chain-transfer
agents. The above hydrophobic substances may be used alone or in a
mixture of two or more.
[0155] Specific examples of the hydrophobic substance include
decane, undecane, dodecane, tridecane, tetradecane, pentadecane,
hexadecane, octadecane, icosane, liquid paraffin, liquid
isoparaffin, a paraffin wax, a polyethylene wax, an olive oil,
polystyrene, polybutylene glycol, and poly(meth)acrylate that have
a mass-average molecular weight (Mw) of 500 to 5000, siloxane
having a mass-average molecular weight (Mw) of 500 to 5000, cetyl
alcohol, stearyl alcohol, palmityl alcohol, behenyl alcohol,
p-methylstyrene, 2-ethylhexyl acrylate, decyl acrylate, stearyl
acrylate, lauryl methacrylate, stearyl methacrylate, and lauryl
mercaptan (n-dodecyl mercaptan).
[0156] In the case where the hydrophobic substance is used, the
amount of the hydrophobic substance used is preferably 0.1 to 10
parts by mass and is further preferably 0.4 to 3 parts by mass
relative to 100 parts by mass of the alkyl (meth)acrylate for the
same reasons as in the first invention.
[0157] <Rubber Component>
[0158] A rubbery polymer (A-II) that is a rubber composite may be
produced by adding another rubber component to the mixture (a-II)
in the production of the rubbery polymer (A-II) according to the
second invention such that the desired properties are not
impaired.
[0159] The descriptions of the rubber component used for producing
the rubbery polymer (A-I) according to the first invention directly
apply to the rubber component used for producing the rubbery
polymer (A-II).
[0160] <Reaction Conditions>
[0161] The miniemulsion formation step and the polymerization step
subsequent to the miniemulsion formation step are conducted under
the same reaction conditions as in the first invention.
[0162] <Particle Size>
[0163] The volume-average particle size of the rubbery polymer
(A-II) according to the second invention which can be produced by
the miniemulsion polymerization method described above is
preferably 1000 nm or less, that is, for example, 100 to 600 nm, in
consideration of polymerization stability. The volume-average
particle size of the rubbery polymer (A-II) is measured by the
method described in Examples below.
[0164] [Graft Copolymer (B-II)]
[0165] The graft copolymer (B-II) according to the second invention
is produced by conducting a graft polymerization step in which at
least one vinyl monomer (b-II) selected from an aromatic vinyl, an
acryl (meth)acrylate, and a vinyl cyanide is grafted to the rubbery
polymer (A-II) according to the second invention prepared by the
above method.
[0166] The graft copolymer (B-II) may further include a vinyl
monomer other than an aromatic vinyl, an alkyl (meth)acrylate, or a
vinyl cyanide which is grafted thereto.
[0167] The descriptions of the graft copolymer (B-I) according to
the first invention directly apply to the suitable ratio between
the amounts of the aromatic vinyl and the vinyl cyanide included in
the vinyl monomer (b-II) used for producing the graft copolymer
(B-II) according to the second invention, the suitable ratio
between the amounts of the rubbery polymer (A-II) and the vinyl
monomer (b-II) used, and the graft polymerization method. The
radical polymerization initiator used in the graft polymerization
and the type and amount of the emulsifier used are also the same as
in the first invention.
[0168] The descriptions of the graft copolymer (B-I) according to
the first invention directly apply to the method for recovering the
graft copolymer (B-II) from the latex containing the graft
copolymer (B-II) produced by emulsion polymerization and the
coagulant used in this process.
[0169] The volume-average particle size of the graft copolymer
(B-II) according to the second invention, which is produced using
the rubbery polymer (A-II) according to the second invention by the
above method, is normally less than 1000 nm. The average particle
size of the graft copolymer (B-II) is measured by the method
described in Examples below.
[0170] [Thermoplastic Resin Composition]
[0171] A method for producing the thermoplastic resin composition
according to the second invention includes using the
above-described graft copolymer (B-II) according to the second
invention. Normally, the graft copolymer (B-II) according to the
second invention is mixed with another thermoplastic resin. The
descriptions of the thermoplastic composition according to the
first invention directly apply to the suitable content of the graft
copolymer (B-II) in the thermoplastic resin composition
(hereinafter, may be referred to as "thermoplastic resin
composition according to the second invention), the type of the
other thermoplastic resin mixed with the graft copolymer (B-II),
the suitable thermoplastic resin, the additive that may optionally
be added to the thermoplastic composition, and a method for
producing the thermoplastic resin composition.
[0172] [Molded Article]
[0173] A thermoplastic resin molded article having excellent impact
resistance may be produced by molding the thermoplastic resin
composition according to the second invention.
[0174] The thermoplastic resin composition according to the second
invention is molded into an article by the same method as the
thermoplastic resin composition according to the first invention.
The preferable method for molding the thermoplastic resin
composition into an article is also the same as in the first
invention.
[0175] A molded article produced by molding the thermoplastic resin
composition according to the second invention has excellent impact
resistance and is suitably used as an automotive interior or
exterior component, an OA instrument, a building material, or the
like.
[0176] A molded article produced by molding the thermoplastic resin
composition according to the second invention may be used in the
following industrial applications: automotive components and, in
particular, paintless interior and exterior components; building
materials, such as a wall material and a window frame; tableware;
toys; electric home appliances, such as a cleaner housing, a
television housing, and an air-conditioner housing; interior
materials; ship materials; and telecommunication equipment
housings.
Embodiment of Third Invention
[0177] The graft copolymer (B-III) according to the third invention
is produced by forming a graft layer (g) on a rubbery polymer
(A-III). The rubbery polymer (A-III) includes an alkyl
(meth)acrylate unit having 1 to 11 carbon atoms, an alkyl
(meth)acrylate unit having 12 to 30 carbon atoms, a multifunctional
monomer unit copolymerizable with the alkyl (meth)acrylates
(hereinafter, this multifunctional monomer may be referred to
simply as "multifunctional monomer"). The graft layer (g) is formed
by grafting at least one vinyl monomer selected from the group
consisting of an aromatic vinyl, an alkyl (meth)acrylate, and a
vinyl cyanide to the rubbery polymer (A-III).
[0178] [Rubbery Polymer (A-III)]
[0179] The rubbery polymer (A-III) (hereinafter, may be referred to
as "rubbery polymer (A-III) according to the third invention")
constituting the graft copolymer (B-III) according to the third
invention is described below.
[0180] The rubbery polymer (A-III) according to the third invention
is produced by performing miniemulsion polymerization that includes
a step in which a pre-emulsion is prepared preferably using a
mixture containing an alkyl (meth)acrylate having 1 to 11 carbon
atoms, an alkyl (meth)acrylate having 12 to 30 carbon atoms, a
multifunctional monomer, and an emulsifier and more preferably
using a mixture containing an alkyl (meth)acrylate having 1 to 11
carbon atoms, an alkyl (meth)acrylate having 12 to 30 carbon atoms,
a multifunctional monomer, a radical polymerization initiator, an
emulsifier, and water and a step in which the emulsion is
polymerized.
[0181] The method for producing the rubbery polymer (A-III)
according to the third invention by miniemulsion polymerization, in
which a pre-emulsion is prepared using a mixture containing an
alkyl (meth)acrylate having 1 to 11 carbon atoms, an alkyl
(meth)acrylate having 12 to 30 carbon atoms, a multifunctional
monomer, a radical polymerization initiator, an emulsifier, and
water and the emulsion is polymerized, is described below.
[0182] The mechanisms of miniemulsion and miniemulsion
polymerization are as described in the sections "Mechanisms of
Miniemulsion" and "Miniemulsion Polymerization" in the first
invention. The descriptions in the above sections directly apply to
the third invention except that the terms "rubbery polymer (A-I)",
"mixture (a-I)", and "graft copolymer (B-I)" are read as "rubbery
polymer (A-III)", "mixture (a-III)", and "graft copolymer (B-III)",
respectively.
[0183] Specifically, examples of the miniemulsion polymerization
method used for producing the rubbery polymer (A-III) according to
the third invention include, but are not limited to, a method
including a step in which monomers including at least an alkyl
(meth)acrylate having 1 to 11 carbon atoms, an alkyl (meth)acrylate
having 12 to 30 carbon atoms, and a multifunctional monomer are
mixed with an emulsifier, and, preferably, a radical polymerization
initiator, a step in which the mixture (hereinafter, may be
referred to as "mixture (a-III)") is formed into a pre-emulsion by
the application of a shearing force, and a step in which the
emulsion is heated to a polymerization initiation temperature to be
polymerized.
[0184] The amount of the water solvent used in the preparation of
the pre-emulsion is also the same as in the first invention
described above.
[0185] <Alkyl (Meth)Acrylate Having 1 to 11 Carbon Atoms>
[0186] Examples of the alkyl (meth)acrylate having 1 to 11 carbon
atoms which constitutes the rubbery polymer (A-III) according to
the third invention include alkyl acrylates, such as methyl
acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate,
benzyl acrylate, and 2-ethylhexyl acrylate; and alkyl
methacrylates, such as butyl methacrylate, hexyl methacrylate, and
2-ethylhexyl methacrylate. Among the above alkyl (meth)acrylates
having 1 to 11 carbon atoms, n-butyl acrylate is preferable because
it enhances the impact resistance of a molded article produced
using the thermoplastic resin composition. The above alkyl
(meth)acrylates having 1 to 11 carbon atoms may be used alone or in
combination of two or more.
[0187] <Alkyl (Meth)acrylate Having 12 to 30 Carbon
Atoms>
[0188] Using an alkyl (meth)acrylate having 12 to 30 carbon atoms,
preferably having 15 to 27 carbon atoms, and more preferably having
18 to 24 carbon atoms in the formation of the pre-emulsion may
further enhance stability. If the number of carbon atoms included
in the alkyl (meth)acrylate is less than 12, variations in particle
size may be increased due to Ostwald ripening and the amount of
coarse particles may be increased as a result of coalescence of oil
microdroplets. This leads to poor appearance of the molded article.
If the number of carbon atoms included in the alkyl (meth)acrylate
is more than 30, the viscosity of the solution is increased and,
consequently, the amount of coarse oil droplets that are not torn
is increased. This leads to poor appearance of the molded
article.
[0189] Examples of the alkyl (meth)acrylate having 12 to 30 carbon
atoms include decyl acrylate, undecyl acrylate, lauryl acrylate,
tridecyl acrylate, myristyl acrylate, pentadecyl acrylate, cetyl
acrylate, stearyl acrylate, isostearyl acrylate, oleyl acrylate,
linoleyl acrylate, nonadecyl acrylate, docodecyl acrylate, behenyl
acrylate, ceryl acrylate, decyl methacrylate, undodecyl
methacrylate, lauryl methacrylate, tridecyl methacrylate, myristyl
methacrylate, pentadecyl methacrylate, cetyl methacrylate, stearyl
methacrylate, isostearyl methacrylate, oleyl methacrylate, linoleyl
methacrylate, nonadecyl methacrylate, docodecyl methacrylate,
behenyl methacrylate, and ceryl methacrylate. Among the above alkyl
(meth)acrylates having 12 to 30 carbon atoms, decyl acrylate,
lauryl acrylate, tridecyl acrylate, stearyl acrylate, docodecyl
acrylate, ceryl acrylate, lauryl methacrylate, and stearyl
methacrylate are preferable. The above alkyl (meth)acrylates having
12 to 30 carbon atoms may be used alone or in a mixture of two or
more.
[0190] The amount of the alkyl (meth)acrylate having 12 to 30
carbon atoms used is preferably 0.1 to 50 parts by mass and is
further preferably 1 to 10 parts by mass relative to 100 parts by
mass of the total amount of the alkyl (meth)acrylate having 1 to 11
carbon atoms and the alkyl (meth)acrylate having 12 to 30 carbon
atoms used. When the amount of the alkyl (meth)acrylate having 12
to 30 carbon atoms used falls within the above range, the amount of
coagulum formed during polymerization is small, which leads to
excellent production stability. Furthermore, excellent moldability
of the thermoplastic resin composition and excellent impact
resistance are achieved in a balanced manner.
[0191] <Multifunctional Monomer>
[0192] The descriptions of the function, specific examples, amount,
and the like of the multifunctional monomer used for producing the
rubbery polymer (A-I) according to the first invention directly
apply to the multifunctional monomer used for producing the rubbery
polymer (A-III) according to the third invention.
[0193] <Emulsifier>
[0194] The descriptions of the specific examples, amount, and the
like of the emulsifier used for producing the rubbery polymer (A-I)
according to the first invention directly apply to the emulsifier
used for producing the rubbery polymer (A-III) according to the
third invention.
[0195] <Radical Polymerization Initiator>
[0196] The descriptions of the specific examples, amount, and the
like of the radical polymerization initiator used for producing the
rubbery polymer (A-I) according to the first invention directly
apply to the radical polymerization initiator used in the
polymerization step subsequent to the pre-emulsion preparation
step.
[0197] <Hydrophobic Substance>
[0198] A hydrophobic substance may be used for producing the
rubbery polymer (A-III) according to the third invention in an
amount at which the desired properties of the third invention are
not impaired. Using a hydrophobic substance in the production of
the pre-emulsion may further enhance the stability with which the
miniemulsion polymerization is performed.
[0199] Examples of the hydrophobic substance include hydrocarbons
having 10 or more carbon atoms; alcohols having 10 or more carbon
atoms; hydrophobic polymers having a mass-average molecular weight
(Mw) of less than 10000; hydrophobic monomers, such as a vinyl
ester of an alcohol having 10 to 30 carbon atoms, a vinyl ether of
an alcohol having 12 to 30 carbon atoms, a vinyl ester of a
carboxylic acid having 10 to 30 carbon atoms (preferably 10 to 22
carbon atoms), and p-alkylstyrene; hydrophobic chain-transfer
agents; and hydrophobic peroxides. The above hydrophobic substances
may be used alone or in a mixture of two or more.
[0200] Specific examples of the hydrophobic substance include
hexadecane, octadecane, icosane, liquid paraffin, liquid
isoparaffin, a paraffin wax, a polyethylene wax, an olive oil,
cetyl alcohol, stearyl alcohol, and polystyrene, poly
(meth)acrylate, and polybutylene glycol that have a mass-average
molecular weight (Mw) of 500 to 10000.
[0201] In the case where the hydrophobic substance is used, the
amount of the hydrophobic substance used is preferably 0.1 to 10
parts by mass and is further preferably 1 to 3 parts by mass
relative to 100 parts by mass of the alkyl (meth)acrylate. If the
amount of the hydrophobic substance used is larger than the above
upper limit, the amount of the gas generated during molding may be
increased.
[0202] <Rubber Component>
[0203] In the production of the rubbery polymer (A-III) according
to the third invention, a rubbery polymer (A-III) that is a rubber
composite may be produced by using another rubber component in the
preparation of the pre-emulsion such that the desired properties
are not impaired. The descriptions of the rubber component used for
producing the rubbery polymer (A-I) according to the first
invention directly apply to the other rubber component.
[0204] <Reaction Conditions>
[0205] The miniemulsion formation step and the polymerization step
subsequent to the miniemulsion formation step are conducted under
the same reaction conditions as in the first invention.
[0206] <Particle Size>
[0207] The volume-average particle size of the rubbery polymer
(A-III) according to the third invention which can be produced by
the miniemulsion polymerization method described above is
preferably 1000 nm or less, that is, for example, 100 to 600 nm, in
consideration of polymerization stability.
[0208] The particle size of the rubbery polymer (A-III) according
to the third invention preferably satisfies the following
conditions (1) and (2) in order to enhance the impact resistance
and appearance of the molded article. In conditions (1) and (2), X
represents volume-average particle size (X), Y represents
upper-frequency boundary 10%-volume particle size (Y) that is the
particle size at which the cumulative frequency calculated from the
upper boundary of a particle size distribution curve reaches 10%,
and Z represents lower-frequency boundary 10%-volume particle size
(Z) that is the particle size at which the cumulative frequency
calculated from the lower boundary of the particle size
distribution curve reaches 10%.
[0209] (1) Volume-average particle size (X) satisfies X.ltoreq.300
nm, upper-frequency boundary 10%-volume particle size (Y) satisfies
Y.ltoreq.1.6 X, and lower-frequency boundary 10%-volume particle
size (Z) satisfies Z.gtoreq.0.5 X.
[0210] (2) Volume-average particle size (X) satisfies X=300 to 1000
nm, upper-frequency boundary 10%-volume particle size (Y) satisfies
Y.ltoreq.1.8 X, and lower-frequency boundary 10%-volume particle
size (Z) satisfies Z.gtoreq.0.4 X.
[0211] The volume-average particle size and particle size
distribution of the rubbery polymer (A-III) are measured by the
method described in Examples below.
[0212] [Graft Copolymer (B-III)]
[0213] The graft copolymer (B-III) according to the third invention
is produced by forming a graft layer (g) on the rubbery polymer
(A-III) according to the third invention prepared by the above
method, the graft layer (g) being produced by grafting at least one
vinyl monomer selected from an aromatic vinyl, an alkyl
(meth)acrylate, and a vinyl cyanide to the rubbery polymer
(A-III).
[0214] The graft layer (g) constituting the graft copolymer (B-III)
according to the third invention is formed by chemically or
physically bonding a part or the entirety of the vinyl monomer
(b-III) to the rubbery polymer (A-III).
[0215] The graft ratio of the graft layer (g) of the graft
copolymer (B-III) can be determined by the following method.
[0216] (Calculation of Graft Ratio)
[0217] To 2.5 g of the graft copolymer (B-III), 80 mL of acetone is
added. The resulting mixture is placed in a hot-water bath at
65.degree. C. to reflux for 3 hours in order to extract a
constituent soluble in acetone. The remaining constituent insoluble
in acetone is separated by centrifugation and dried. The mass of
the dried acetone-insoluble constituent is measured. The mass
proportion of the acetone-insoluble substance in the graft
copolymer is calculated. The graft ratio is calculated using the
following formula on the basis of the mass proportion of the
acetone-insoluble substance in the graft copolymer.
Graft ratio (%)=(Mass proportion of acetone-insoluble
substance-Mass proportion of rubbery polymer)/(Mass proportion of
rubbery polymer).times.100 [Math. 1]
[0218] The graft ratio of the graft copolymer (B-III) according to
the third invention is preferably 10% to 90% and is particularly
preferably 20% to 80%. When the graft ratio of the graft copolymer
(B-III) falls within the above range, a molded article having good
impact resistance and good appearance may be produced.
[0219] The graft layer (g) may further include a vinyl monomer
other than an aromatic vinyl, an alkyl (meth)acrylate, or a vinyl
cyanide.
[0220] The descriptions of the graft copolymer (B-I) according to
the first invention directly apply to the suitable ratio between
the amounts of the aromatic vinyl and the vinyl cyanide included in
the vinyl monomer (b-III) used for producing the graft layer (g) of
the graft copolymer (B-III) according to the third invention, the
suitable ratio between the amounts of the rubbery polymer (A-III)
and the vinyl monomer (b-III) used, and the graft polymerization
method. The radical polymerization initiator used in the graft
polymerization and the type and amount of the emulsifier used are
also the same as in the first invention.
[0221] The descriptions of the graft copolymer (B-I) according to
the first invention directly apply also to the method for
recovering the graft copolymer (B-III) from the latex containing
the graft copolymer (B-III) produced by emulsion polymerization and
the coagulant used in this process.
[0222] The volume-average particle size of the graft copolymer
(B-III) according to the third invention, which is produced using
the rubbery polymer (A-III) according to the third invention by the
above method, is normally less than 1000 nm. The average particle
size of the graft copolymer (B-III) is measured by the method
described in Examples below.
[0223] [Thermoplastic Resin Composition]
[0224] A method for producing the thermoplastic resin composition
according to the third invention includes using the above-described
graft copolymer (B-III) according to the third invention. Normally,
the graft copolymer (B-III) according to the third invention is
mixed with another thermoplastic resin. The descriptions of the
thermoplastic composition according to the first invention directly
apply to the suitable content of the graft copolymer (B-III) in 100
parts by mass of the thermoplastic resin composition (hereinafter,
may be referred to as "thermoplastic resin composition according to
the third invention), the type of the other thermoplastic resin
mixed with the graft copolymer (B-III), the suitable thermoplastic
resin, the additive that may optionally be added to the
thermoplastic composition, and a method for producing the
thermoplastic resin composition.
[0225] [Molded Article]
[0226] A thermoplastic resin molded article having excellent impact
resistance may be produced by molding the thermoplastic resin
composition according to the third invention.
[0227] The thermoplastic resin composition according to the third
invention is molded into an article by the same method as the
thermoplastic resin composition according to the first invention.
The preferable method for molding the thermoplastic resin
composition into an article is also the same as in the first
invention.
[0228] A molded article according to the third invention produced
by molding the thermoplastic resin composition according to the
third invention has excellent impact resistance and excellent
appearance and is suitably used as an automotive interior or
exterior component, an OA instrument, a building material, or the
like.
[0229] A molded article according to the third invention produced
by molding the thermoplastic resin composition according to the
third invention may be used in the following industrial
applications: automotive components and, in particular, paintless
interior and exterior components; building materials, such as a
wall material and a window frame; tableware; toys; electric home
appliances, such as a cleaner housing, a television housing, and an
air-conditioner housing; interior materials; ship materials; and
telecommunication equipment housings.
EXAMPLES
[0230] The present invention is described more specifically with
reference to Synthesis examples, Examples, and Comparative examples
below. The present invention is not limited by Examples below and
various modifications can be made within the scope of the
invention.
[0231] Hereinafter, the term "parts" refers to "parts by mass" and
the symbol "%" refers to "% by mass".
Synthesis Examples, Examples, and Comparative Examples of First
Invention
[Hydrophobic Substance]
[0232] The hydrophobic substances used were liquid paraffin
"MORESCO WHITE", Model Nos. "P-40", "P-100", "P-120", "P-150", and
"P-350P", produced by MORESCO Corporation; paraffin waxes "Paraffin
Wax", Model Nos. "115", "125", and "135", produced by NIPPON SEIRO
CO., LTD.; and hexadecane produced by Wako Pure Chemical
Industries, Ltd. Tables 1A and 1B summarize the viscosities of the
above hydrophobic substances.
[0233] [Measurement of Volume-Average Particle Size]
[0234] The average particle sizes of rubbery polymers (A-I-1) to
(A-I-11) and volume-average particle sizes of graft copolymers
(B-I-1) to (B-I-11) were determined by dynamic light scattering
method using Nanotrac UPA-EX150 produced by NIKKISO Co., Ltd.
Production of Rubbery Polymer
Synthesis Example I-1: Production of Rubbery Polymer (A-I-1)
[0235] A rubbery polymer (A-I-1) was produced using the following
materials.
[0236] [Materials]
TABLE-US-00001 n-Butyl acrylate 100 parts MORESCO WHITE "P-60" 2.4
parts Dipotassium alkenyl succinate 2.0 parts Allyl methacrylate
0.2 parts 1,3-Butylene dimethacrylate 0.5 parts t-Butyl
hydroperoxide 0.25 parts Ferrous sulfate 0.0002 parts Sodium
formaldehyde sulfoxylate 0.33 parts Disodium
ethylenediaminetetraacetate 0.0004 parts Distilled water 406
parts
[0237] Distilled water, n-butyl acrylate, MORESCO WHITE "P-60",
dipotassium alkenyl succinate, allyl methacrylate, 1,3-butylene
dimethacrylate, and t-butyl hydroperoxide were charged into a
reactor equipped with a reagent injector, a condenser, a jacket
heater, and a stirrer. The resulting mixture was subjected to an
ultrasonic wave treatment using ULTRASONIC HOMOGENIZER US-600
produced by NIHONSEIKI KAISHA LTD. with an amplitude of 35 .mu.m at
room temperature for 20 minutes to form a pre-emulsion (a-I-1). The
volume-average particle size of the resulting latex was 300 nm.
[0238] After the pre-emulsion (a-I-1) had been heated to 60.degree.
C., ferrous sulfate, sodium formaldehyde sulfoxylate, and disodium
ethylenediaminetetraacetate were added to the pre-emulsion (a-I-1)
in order to initiate radical polymerization. The liquid temperature
was increased to 78.degree. C. as a result of the polymerization of
the acrylate component. The temperature was maintained to be
70.degree. C. for 30 minutes in order to complete the
polymerization of the acrylate component. Hereby, a latex
containing a rubbery polymer (A-I-I) having a solid content of
18.7% and a volume-average particle size of 300 nm was
prepared.
Synthesis Examples I-2 to I-10: Production of Rubbery Polymers
(A-I-2) to (A-I-10)
[0239] Latexes each of which contained a specific one of rubbery
polymers (A-I-2) to (A-I-10) having a solid content of 18.7% and a
volume-average particle size of 300 nm were prepared as in
Synthesis example I-1, except that the hydrophobic substances
described in Tables 1A and 1B were used instead.
Synthesis Example I-11: Production of Rubbery Polymer (A-I-11)
[0240] A rubbery polymer (A-I-11) was produced using the following
materials.
[0241] [Materials]
TABLE-US-00002 n-Butyl acrylate 100 parts Allyl methacrylate 0.2
parts 1,3-Butylene dimethacrylate 0.5 parts t-Butyl hydroperoxide
0.25 parts Ferrous sulfate 0.0002 parts Sodium formaldehyde
sulfoxylate 0.33 parts Disodium ethylenediaminetetraacetate 0.0004
parts Dipotassium alkenyl succinate 2.0 parts Distilled water 406
parts
[0242] Distilled water and dipotassium alkenyl succinate were
charged into a reactor equipped with a reagent injector, a
condenser, a jacket heater, and a stirrer. After the temperature
had been increased to 60.degree. C., ferrous sulfate, sodium
formaldehyde sulfoxylate, and disodium ethylenediaminetetraacetate
were added to the reactor. Then, a liquid mixture of n-butyl
acrylate, allyl methacrylate, 1,3-butylene dimethacrylate, and
t-butyl hydroperoxide was added dropwise to the reactor with a pump
over 300 minutes. The temperature was increased to 80.degree. C.
After the addition of the liquid mixture had been completed, the
temperature was maintained to be 70.degree. C. for 30 minutes in
order to complete the polymerization of the acrylate component.
Hereby, a latex containing a rubbery polymer (A-I-11) was prepared.
The latex containing the rubbery polymer (A-I-11) had a solid
content of 18.4% and a volume-average particle size of 300 nm.
TABLE-US-00003 TABLE 1A For first invention A-I-2 A-I-3 A-I-4 A-I-5
A-I-6 A-I-7 A-I-8 Liquid Liquid Liquid Liquid Paraffin Paraffin
Paraffin paraffin paraffin paraffin paraffin Wax Wax Wax P-100
P-120 P-150 P-350P 135 125 115 19 23.5 30.1 67.7 -- -- -- -- -- --
-- 3.9 3.3 3 300 300 300 300 300 300 300
TABLE-US-00004 TABLE 1B Rubbery polymer A-I-9 A-I-10 A-I-11
Hydrophobic Type Liquid Hexadecane Not substance used paraffin used
Model No. P-40 -- Kinematic 40.degree. C. 4.3 -- viscosity
100.degree. C. -- 1.2 (mm.sup.2/s) Volume-average particle size(nm)
300 300 Remarks For comparison
Production and Evaluations of Graft Copolymer
Example I-1: Production of Graft Copolymer (B-I-1)
[0243] Raw materials were charged into a reactor equipped with a
reagent injector, a condenser, a jacket heater, and a stirrer in
the amounts described below. After the inside of the reactor had
been purged with nitrogen to a sufficient degree, the inside
temperature of the reactor was increased to 70.degree. C. while the
inside of the reactor was stirred.
[0244] [Materials]
TABLE-US-00005 Water (including water contained in the rubbery
polymer 230 parts latex) Latex of the rubbery polymer (A-I-1) 50
parts (as solid content) Dipotassium alkenyl succinate 0.2 parts
Sodium formaldehyde sulfoxylate 0.3 parts Ferrous sulfate 0.001
parts Disodium ethylenediaminetetraacetate 0.003 parts
[0245] Subsequently, a liquid mixture containing acrylonitrile
(AN), styrene (ST), and t-butyl hydroperoxide in the amounts below
was added dropwise to the reactor over 100 minutes, while the
temperature was increased to 80.degree. C.
[0246] [Materials]
TABLE-US-00006 Acrylonitrile 12.5 parts Styrene 37.5 parts t-Butyl
hydroperoxide 0.2 parts
[0247] After the addition of the liquid mixture had been completed,
the temperature was maintained to be 80.degree. C. for 30 minutes
and subsequently reduced. Hereby, a latex containing a graft
copolymer (B-I-1) was prepared. The latex of the graft copolymer
(B-I-1) had a solid content of 29.7% and a volume-average particle
size of 340 nm.
[0248] Then, 100 parts of a 1.5% aqueous sulfuric acid solution was
heated to 80.degree. C. While the aqueous solution was stirred, 100
parts of the latex containing the graft copolymer (B-I-1) was
gradually added dropwise to the aqueous solution in order to
solidify the graft copolymer (B-I-1). Subsequently, the temperature
was further increased to 95.degree. C. and maintained to be
95.degree. C. for 10 minutes.
[0249] The resulting solid was dehydrated, cleaned, and dried.
Hereby, a powdery graft copolymer (B-I-1) was prepared.
Examples I-2 to I-8 and Comparative Examples I-1 to I-3: Production
of Graft Copolymers (B-I-2) to (B-I-11)
[0250] Graft copolymers (B-I-2) to (B-I-11) were prepared as in
Example I-1, except that the latexes each of which contained a
specific one of the rubbery polymers (A-I-2) to (A-I-11) were used
instead of the latex of the rubbery polymer (A-I-1). Tables 2A and
2B summarize the volume-average particle sizes of the graft
copolymers (B-I-2) to (B-I-11).
[0251] <Production of Thermoplastic Resin Composition>
[0252] With 40 parts of a specific one of the graft copolymers
(B-I-1) to (B-I-11), 60 parts of an acrylonitrile-styrene copolymer
("UMG AXS Resin S102N" produced by UMG ABS, LTD.), which was
produced by suspension polymerization, was mixed using a Henschel
mixer. The resulting mixture was charged into an extruder heated at
240.degree. C. and kneaded to form a pellet.
[0253] <Preparation of Test Piece>
[0254] The pellet formed in Production of Thermoplastic Resin
Composition above was molded into a shape using a four-ounce
injection molding machine (produced by The Japan Steel Works, LTD.)
under the following conditions: cylinder temperature: 240.degree.
C., metal mold temperature: 60.degree. C., injection rate: 20
g/sec. Hereby, a rod-like molded body 1 having a length of 80 mm, a
width of 10 mm, and a thickness of 4 mm was prepared.
[0255] <Evaluations>
[0256] (Measurement of Charpy Impact Strength)
[0257] The Charpy impact strength of the molded body 1 was measured
at 23.degree. C. and -30.degree. C. in accordance with ISO 179.
[0258] (Measurement of Melt Volume Rate (MVR))
[0259] The MVR of the pellet formed in Production of Thermoplastic
Resin Composition above was measured under the conditions of
220.degree. C.-98N in accordance with ISO 1133. The MVR of the
pellet is a measure of the fluidity of the thermoplastic resin
composition.
[0260] (Gas Generation and Deposition Test)
[0261] Injection molding of the pellet of the resin composition
formed in Production of Thermoplastic Resin Composition above was
performed using the metal mold 10 illustrated in FIG. 1, in which a
molten resin ejected through a sprue 11 flows through runners 12
and 13 in two directions and subsequently ejected from side gates
14 and 15, and the portions of the molten resin meet each other in
the mold to form a weld plane. In this process, a short shot was
made such that a molten resin 20 did not form a weld plane and
remained unfused at the center of the inside of the metal mold 10.
Specifically, injection molding was performed in 100 shots such
that a gas space was formed inside the metal mold 10. Subsequent to
the injection molding, the amount of an oily deposit adhered to a
portion 10a of the metal mold at which the unfused portion was
exposed was measured as the amount of gas deposited. The gas
generated during molding and deposited on the metal mold in the
form of an oily deposit migrates onto the molded article side and
degrades the appearance of the molded article. Therefore, the oily
deposits adhered on the metal mold need to be removed by cleaning
on a regular basis. This leads to poor continuous moldability. The
smaller the amount of gas deposited, the higher the continuous
moldability.
[0262] Tables 2A and 2B summarize the evaluation results.
TABLE-US-00007 TABLE 2A Example Example Example Example Example
Example Example Example I-1 I-2 I-3 I-4 I-5 I-6 I-7 I-8 Graft Type
of graft B-I-1 B-I-2 B-I-3 B-I-4 B-I-5 B-I-6 B-I-7 B-I-8 copolymer
copolymer Rubbery 50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/
50/12.5/ 50/12.5/ 50/12.5/ polymer/AN/ST 37.5 37.5 37.5 37.5 37.5
37.5 37.5 37.5 (part) Volume-average 340 340 340 340 340 340 340
340 particle size (nm) Rubbery Type A-I-1 A-I-2 A-I-3 A-I-4 A-I-5
A-I-6 A-I-7 A-I-8 polymer Hydrophobic Type Liquid Liquid Liquid
Liquid Liquid Paraffin Paraffin Paraffin substance paraffin
paraffin paraffin paraffin paraffin Wax Wax Wax used Model No. P-60
P-100 P-120 P-150 P-350P 135 125 115 Kinematic 40.degree. C. 9.7 19
23.5 30.1 67.7 -- -- -- viscosity 100.degree. C. -- -- -- -- -- 3.9
3.3 3 (mm.sup.2/s) Evaluation Charpy impact 23.degree. C. 11 12 12
13 13 13 13 12 results strength (kJ/m.sup.2) -30.degree. C. 2 2 2 3
3 2 2 2 MVR 22 21 21 20 20 19 19 20 (cm.sup.3/10 min) Amount of gas
deposited (mg) 0.3 0.3 0.2 0.1 0.1 0.1 0.1 0.1
TABLE-US-00008 TABLE 2B Example Example Example I-1 I-2 I-3 Graft
copolymer Type of graft B-I-9 B-I-10 B-I-11 copolymer Rubbery
50/12.5/ 50/12.5/ 50/12.5/ polymer/AN/ST 37.5 37.5 37.5 (part)
Volume-average 340 340 340 particle size (nm) Rubbery polymer Type
A-I-9 A-I-10 A-I-11 Hydrophobic Type Liquid Hexadecane Not used
substance paraffin used Model No. P-40 -- Kinematic 40.degree. C.
4.3 -- viscosity 100.degree. C. -- 1.2 (mm.sup.2/s) Evaluation
results Charpy impact 23.degree. C. 9 9 6 strength (kJ/m.sup.2)
-30.degree. C. 1 1 1 MVR 22 22 19 (cm.sup.3/10 min) Amount of gas
deposited (mg) 0.5 0.5 0.1
[0263] The results obtained in Examples and Comparative PGP
examples confirm the following facts.
[0264] The thermoplastic resin compositions prepared in Examples
I-1 to I-8 were excellent in terms of impact resistance, fluidity
(moldability), and the amount of gas deposited (continuous
moldability).
[0265] The thermoplastic resin compositions prepared in Comparative
examples I-1 to I-3 were poor in terms of impact resistance,
fluidity, or gas deposition. Specifically, in Comparative examples
I-1 and I-2, where the kinematic viscosity of the hydrophobic
substance used for producing the rubbery polymer were outside the
range of the first invention, poor results were obtained in terms
of gas deposition and impact resistance. In Comparative example
I-3, where the hydrophobic substance was not used, impact
resistance was significantly poor.
Synthesis Examples, Examples, and Comparative Examples of Second
Invention
[Oil-Soluble Initiator]
[0266] The following oil-soluble initiators were used: peroxides
produced by NOF CORPORATION, such as "PERHEXYL ND (t-hexyl peroxy
neodecanoate)", "PEROYL 335-75(S) (di(3,3,5-trimethylhexanoyl)
peroxide)", "PERBUTYL P
(.alpha.,.alpha.'-bis(t-butylperoxy)diisopropylbenzene)", "PEROYL
TCP (bis(4-t-butylcyclohexyl) peroxydicarbonate)", "PEROYL L
(dilauroyl peroxide)", "PERTETRA A
(2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane)", "NYPER BW
(benzoyl peroxide)", and "PERBUTYL H-69 (t-butyl hydroperoxide)";
and azo compounds produced by Wako Pure Chemical Industries, Ltd.,
such as "VE-073 (dimethyl 1,1'-azobis(1-cyclohexane carboxylate))"
and "V-65 (2,2'-azobis(2,4-dimethyl valeronitrile))". Tables 3A and
3B summarize the numbers of carbon atoms included in the above
oil-soluble initiators.
[0267] [Evaluation of Stability of Pre-Emulsion]
[0268] A pre-emulsion that was formed into a miniemulsion was
charged into a graduated cylinder made of glass. The pre-emulsion
was left to stand until the water phase and the oil phase were
separated from each other. The stability of the pre-emulsion was
evaluated in accordance with the following criterion. A
pre-emulsion evaluated as ".DELTA.", ".largecircle.", or
".circle-w/dot." was considered to be stable.
[0269] .circle-w/dot.: Separation did not occur even after the
pre-emulsion had been left to stand for one week or more.
[0270] .largecircle.: Separation occurred after the pre-emulsion
had been left to stand for one day or more and less than one
week.
[0271] .DELTA.: Separation occurred after the pre-emulsion had been
left to stand for 5 hours or more and less than 24 hours.
[0272] x: Separation occurred after the pre-emulsion had been left
to stand for less than 5 hours.
[0273] [Measurement of Volume-Average Particle Size]
[0274] The average particle sizes of rubbery polymers (A-II-1) to
(A-II-10) and the volume-average particle sizes of graft copolymers
(B-II-1) to (B-II-10) were determined by dynamic light scattering
method using Nanotrac UPA-EX150 produced by NIKKISO Co., Ltd.
[0275] [Measurement of Coagulum Content]
[0276] A latex containing a specific one of the rubbery polymers
(A-II-1) to (A-II-10) and the graft copolymers (B-II-1) to
(B-II-10) was filtered through a 100-mesh metal screen. Coagulum
remaining on the 100-mesh metal screen was dried. The mass of the
dried coagulum was measured. The ratio (mass %) of the mass of the
coagulum to the mass of the specific one of the rubbery polymers
(A-II-1) to (A-II-10) and the graft copolymers (B-II-1) to
(B-II-10) was calculated. The smaller the content of coagulum, the
higher the production stability of the latex of the rubbery polymer
or graft copolymer.
[0277] [Measurement of Storage Stability]
[0278] A latex of a specific one of the graft copolymers (B-II-1)
to (B-II-10) was filtered through a 100-mesh metal screen. The
filtrate was left to stand at 25.degree. C. for 10 days or 60 days.
Subsequently, whether or not precipitates were present in the latex
was determined. The storage stability of the latex was evaluated in
accordance with the following criterion. A latex of a graft
copolymer evaluated as ".DELTA.", ".largecircle.", or
"z.circle-w/dot." was considered to be stable.
[0279] .circle-w/dot.: No precipitate was present even when the
filtrate was left to stand for 60 days.
[0280] .largecircle.: No precipitate was present even when the
filtrate was left to stand for 10 days.
[0281] .DELTA.: A trace amount of precipitate was present.
[0282] x: A large amount of precipitate was present.
Production of Rubbery Polymer
Synthesis Example II-1: Production of Rubbery Polymer (A-II-1)
[0283] A rubbery polymer (A-II-1) was produced using the following
materials.
[0284] [Materials]
TABLE-US-00009 n-Butyl acrylate 100 parts Dipotassium alkenyl
succinate 2.0 parts Allyl methacrylate 0.2 parts 1,3-Butylene
dimethacrylate 0.5 parts Hexadecane 0.5 parts PERHEXYL ND 0.4 parts
Distilled water 406 parts
[0285] Distilled water, n-butyl acrylate, dipotassium alkenyl
succinate, allyl methacrylate, 1,3-butylene dimethacrylate,
hexadecane, and PERHEXYL ND were charged into an autoclave equipped
with a reagent injector, a jacket heater, and a stirrer. The
resulting mixture was subjected to an ultrasonic wave treatment
using ULTRASONIC HOMOGENIZER US-600 produced by NIHONSEIKI KAISHA
LTD. with an amplitude of 35 .mu.m at room temperature for 20
minutes to form a pre-emulsion (a-II-1). The volume-average
particle size of the resulting latex was 300 nm. The results of
evaluation of the stability of the pre-emulsion (a-II-1) confirmed
that the pre-emulsion (a-II-1) had good stability.
[0286] The pre-emulsion (a-II-1) was heated to 50.degree. C. in
order to initiate radical polymerization. The liquid temperature
was increased to 68.degree. C. as a result of the polymerization of
the acrylate component. The temperature was maintained to be
70.degree. C. for 30 minutes in order to complete the
polymerization of the acrylate component. Hereby, a latex
containing a rubbery polymer (A-II-1) having a solid content of
17.9%, a coagulum content of 0.90%, and a volume-average particle
size of 320 nm was prepared.
Synthesis Examples II-2 to II-9: Production of Rubbery Polymers
(A-II-2) to (A-II-9)
[0287] Latexes each of which contained a specific one of rubbery
polymers (A-II-2) to (A-II-9) were prepared as in Synthesis example
II-1, except that the oil-soluble initiators described in Tables 3A
and 3B were used instead and the polymerization temperature was
changed as described in Tables 3A and 3B. Tables 3A and 3B
summarize the results of evaluation of the stability of the
pre-emulsion and the solid content, coagulum content, and
volume-average particle size of the rubbery polymer latex.
Synthesis Example II-10: Production of Rubbery Polymer
(A-II-10)
[0288] A rubbery polymer (A-II-10) was produced using the following
materials.
[0289] [Materials]
TABLE-US-00010 n-Butyl acrylate 100 parts Allyl methacrylate 0.2
parts 1,3-Butylene dimethacrylate 0.5 parts PERBUTYL H-69 0.25
parts Ferrous sulfate 0.0002 parts Sodium formaldehyde sulfoxylate
0.33 parts Disodium ethylenediaminetetraacetate 0.0004 parts
Dipotassium alkenyl succinate 2.0 parts Distilled water 406
parts
[0290] Distilled water, dipotassium alkenyl succinate, 30 parts of
n-butyl acrylate, 0.06 parts of allyl methacrylate, 0.15 parts of
1,3-butylene dimethacrylate, and 0.05 parts of PERBUTYL H-69 were
charged into a nitrogen-purged reactor equipped with a reagent
injector, a condenser, a jacket heater, and a stirrer. After the
temperature had been increased to 60.degree. C., ferrous sulfate,
sodium formaldehyde sulfoxylate, and disodium
ethylenediaminetetraacetate were added to the reactor. The
resulting mixture was reacted for 60 minutes. Then, a liquid
mixture of 70 parts of n-butyl acrylate, 0.14 parts of allyl
methacrylate, 0.35 parts of 1,3-butylene dimethacrylate, and 0.2
parts of t-butyl hydroperoxide was added dropwise to the reactor
with a pump over 300 minutes. The temperature was increased to
80.degree. C. After the addition of the liquid mixture had been
completed, the temperature was maintained to be 70.degree. C. for
30 minutes in order to complete the polymerization of the acrylate
component. Hereby, a latex containing a rubbery polymer (A-II-10)
was prepared. The amount of time required for producing the latex
was 420 minutes. The latex containing the rubbery polymer (A-II-10)
had a solid content of 18.0%, a coagulum content of 1.2%, and a
volume-average particle size of 300 nm.
Production of Graft Copolymer
Example II-i-1: Production of Graft Copolymer (B-II-1)
[0291] Raw materials were charged into a reactor equipped with a
reagent injector, a condenser, a jacket heater, and a stirrer in
the amounts described below. After the inside of the reactor had
been purged with nitrogen to a sufficient degree, the inside
temperature of the reactor was increased to 70.degree. C. while the
inside of the reactor was stirred.
[0292] [Materials]
TABLE-US-00011 Water (including water contained in the rubbery
polymer 230 parts latex) Latex containing the rubbery polymer
(A-II-1) 50 parts (as solid content) Dipotassium alkenyl succinate
0.2 parts Sodium formaldehyde sulfoxylate 0.3 parts Ferrous sulfate
0.001 parts Disodium ethylenediaminetetraacetate 0.003 parts
[0293] Subsequently, a liquid mixture containing acrylonitrile
(AN), styrene (ST), and t-butyl hydroperoxide in the amounts below
was added dropwise to the reactor over 100 minutes, while the
temperature was increased to 80.degree. C.
[0294] [Materials]
TABLE-US-00012 Acrylonitrile 12.5 parts Styrene 37.5 parts PERBUTYL
H-69 0.2 parts
[0295] After the addition of the liquid mixture had been completed,
the temperature was maintained to be 80.degree. C. for 30 minutes
and subsequently reduced. Hereby, a latex containing a graft
copolymer (B-II-1) was prepared. The latex of the graft copolymer
(B-II-1) had a solid content of 29.7%, a coagulum content of 0.02%,
and a volume-average particle size of 370 nm. Tables 3A and 3B
summarize the storage stability of the graft copolymer
(B-II-1).
[0296] Then, 100 parts of a 1.5% aqueous sulfuric acid solution was
heated to 80.degree. C. While the aqueous solution was stirred, 100
parts of the latex containing the graft copolymer (B-II-1) was
gradually added dropwise to the aqueous solution in order to
solidify the graft copolymer (B-II-1). Subsequently, the
temperature was further increased to 95.degree. C. and maintained
to be 95.degree. C. for 10 minutes.
[0297] The resulting solid was dehydrated, cleaned, and dried.
Hereby, a powdery graft copolymer (B-II-1) was prepared.
Examples II-i-2 to II-i-7 and Comparative Examples II-i-1 to
II-i-3: Production of Graft Copolymers (B-II-2) to (B-II-10)
[0298] Graft copolymers (B-II-2) to (B-II-10) were prepared as in
Example II-i-1, except that the latexes each of which contained a
specific one of the rubbery polymers (A-II-2) to (A-II-10) were
used instead of the latex of the rubbery polymer (A-II-1). Tables
3A and 3B summarize the volume-average particle sizes, storage
stability, and coagulum content of each of the graft copolymers
(B-II-2) to (B-II-10).
TABLE-US-00013 TABLE 3A Example Example Example Example Example
Example Example II-i-1 II-i-2 II-i-3 II-i-4 II-i-5 II-i-6 II-i-7
Rubbery polymer A-II-1 A-II-2 A-II-3 A-II-4 A-II-5 A-II-6 A-II-7
Oil-soluble Type Peroxide Peroxide Peroxide Peroxide Peroxide
Peroxide Azo compound initiator Product PERHEXYL PEROYL PERBUTYL
PEROYL PEROYL PERTETRA 74 name ND 335-75(S) P TCP L A VE-073 Number
of 16 18 20 22 24 31 16 carbon atoms Stablity of .DELTA.
.largecircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .DELTA. pre-emulsion Polymerization 50 65 125 45
65 100 78 temperature (.degree. C.) Volume-average 320 320 310 300
300 300 330 particle size (nm) Solid content (%) 17.9 18.6 18.9 19
19.1 19.1 17.5 Coagulum content (%) 0.90 0.30 0.10 0.02 0.01 0.01
0.9 Graft copolymer B-1 B-2 B-3 B-4 B-5 B-6 B-7 Volume-average 370
370 340 340 340 340 380 particle size (nm) Storage stability
.DELTA. .DELTA. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .DELTA. Coagulum content (%) 0.02 0.02 0.02 0.01
0.01 0.01 0.01
TABLE-US-00014 TABLE 3B Comparative Comparative Comparative example
example example II-i-1 II-i-2 II-i-3 Rubbery polymer A-II-8 A-II-9
A-II-10 Oil-soluble Type Peroxide Azo compound Peroxide initiator
Product NYPER V-65 PERBUTYL name BW H-69 Number of 14 14 4 carbon
atoms Stability of x x -- pre-emulsion Polymerization 78 55 70
temperature (.degree. C.) Volume-average 340 350 300 particle
size(nm) Solid content(%) 14.2 17.2 18 Coagulum content(%) 5.0 2.0
1.2 Graft copolymer B-8 B-9 B-10 Volume-average 400 400 340
particle size(nm) Storage stability x x x Coagulum content(%) 0.10
0.09 0.03
Examples II-ii-1 to II-ii-7, Comparative Examples II-ii-1 to
II-ii-3: Production of Thermoplastic Resin Composition
[0299] With 40 parts of a specific one of the graft copolymers
(B-II-1) to (B-II-10), 60 parts of an acrylonitrile-styrene
copolymer ("UMG AXS Resin S102N" produced by UMG ABS, LTD.), which
was produced by suspension polymerization, was mixed using a
Henschel mixer. The resulting mixture was charged into an extruder
heated at 240.degree. C. and kneaded to form a pellet.
[0300] <Preparation of Test Piece>
[0301] The pellet formed in Production of Thermoplastic Resin
Composition above was molded into a shape using a four-ounce
injection molding machine (produced by The Japan Steel Works, LTD.)
under the following conditions: cylinder temperature: 240.degree.
C., metal mold temperature: 60.degree. C., injection rate: 20
g/sec. Hereby, a rod-like molded body having a length of 80 mm, a
width of 10 mm, and a thickness of 4 mm was prepared.
[0302] <Evaluations>
(Measurement of Charpy Impact Strength)
[0303] The Charpy impact strength of the molded body was measured
at 23.degree. C. and -30.degree. C. in accordance with ISO 179.
[0304] (Measurement of Melt Volume Rate (MVR))
[0305] The MVR of the pellet of the thermoplastic resin composition
was measured under the conditions of 220.degree. C.-98N in
accordance with ISO 1133. The MVR of the pellet is a measure of the
fluidity of the thermoplastic resin composition.
[0306] Tables 4A and 4B summarize the evaluation results.
TABLE-US-00015 TABLE 4A Example Example Example Example Example
Example Example II-ii-1 II-ii-2 II-ii-3 II-ii-4 II-ii-5 II-ii-6
II-ii-7 Graft Type of graft B-II-1 B-II-2 B-II-3 B-II-4 B-II-5
B-II-6 B-II-7 co- copolymer polymer Rubbery 50/12.5/ 50/12.5/
50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/ polymer/AN/ST 37.5
37.5 37.5 37.5 37.5 37.5 37.5 (part) Volumne-average 370 370 340
340 340 340 380 particle size (nm) Rubbery Type A-II-1 A-II-2
A-II-3 A-II-4 A-II-5 A-II-6 A-II-7 polymer Polymerization Mini-
Mini- Mini- Mini- Mini- Mini- Mini- method emulsion emulsion
emulsion emulsion emulsion emulsion emulsion poly- poly- poly-
poly- poly- poly- poly- merization merization merization merization
merization merization merization Oil-soluble Type Peroxide Peroxide
Peroxide Peroxide Peroxide Peroxide Azo initiator compound Product
PER- PEROYL PER- PEROYL PEROYL PER- VE-073 name HEXYL 335-75(S)
BUTYL TCP L TETRA ND P A Number of 16 18 20 22 24 31 16 carbon
atoms Eval- Charpy 23.degree. C. 12 12 15 15 15 15 12 uation impact
-30.degree. C. 3 3 4 4 4 4 3 results strength (kJ/m.sup.2) MVR 31
31 30 30 30 30 31 (cm.sup.3/10 min)
TABLE-US-00016 TABLE 4B Comparative Comparative Comparative example
example example II-ii-1 II-ii-2 HII-ii-3 Graft Type of graft
copolymer B-II-8 B-II-9 B-II-10 copolymer Rubbery polymer/ 50/12.5/
50/12.5/ 50/12.5/ AN/ST (part) 37.5 37.5 37.5 Volume-average
particle 400 400 340 size (nm) Rubbery Type A-II-8 A-II-9 A-II-10
polymer Polymerization method Miniemulsion Miniemulsion Emulsion
polymerization polymerization polymerization Oil-soluble Type
Peroxide Azo compound Peroxide initiator Product NYPER V-65
PERBUTYL name BW H-69 Number of 14 14 4 carbon atoms Evaluation
Charpy impact 23.degree. C. 9 9 7 results strength -30.degree. C. 3
3 1 (kJ/m.sup.2) MVR 32 32 22 (cm.sup.3/10 min)
[0307] The results obtained in Examples and Comparative examples
confirm the following facts.
[0308] In Examples II-i-1 to II-i-7, the stability of the
pre-emulsion was high. Furthermore, the latex of the graft
copolymer (B-II) was excellent in terms of coagulum (production
stability) and storage stability.
[0309] In Comparative examples II-i-1 to II-i-3, poor results were
obtained in terms of the stability of pre-emulsion, coagulum
content, or storage stability. Specifically, in Comparative
examples II-i-1 and II-i-2, where the number of carbon atoms
included in the oil-soluble initiator was outside the range of the
second invention, the pre-emulsion had poor stability and a large
amount of coagulum was formed in the polymerization step. In
addition, storage stability was poor. In Comparative example
II-i-3, where a polymerization method other than miniemulsion
polymerization was used, inhomogeneous particles were formed. This
resulted in poor storage stability.
[0310] The thermoplastic resin compositions prepared in Examples
II-ii-1 to II-ii-7, which were prepared using the graft copolymers
(B-II) prepared in Examples II-i-1 to II-i-7, had excellent impact
resistance and excellent fluidity. In Comparative examples II-ii-1
and II-ii-2, where the graft copolymer used had poor production
stability and poor storage stability, inhomogeneous particles were
formed. This resulted in poor impact resistance. In Comparative
example II-ii-3, where emulsion polymerization was used, a
homogeneous polymer failed to be produced. This resulted in poor
impact resistance and poor fluidity.
Production Examples, Examples, and Comparative Examples of Third
Invention
[Measurement of Volume-Average Particle Size]
[0311] The volume-average particle sizes of rubbery polymers
(A-III-1) to (A-III-10) and graft copolymers (B-III-1) to
(B-III-10) were determined by dynamic light scattering method using
Nanotrac UPA-EX150 produced by NIKKISO Co., Ltd.
[0312] The particle size distribution was determined by the same
method as described above. The ratios of the upper-frequency
boundary 10%-volume particle size (Y) and the lower-frequency
boundary 10%-volume particle size (Z) relative to the
volume-average particle size (X) were calculated.
[0313] [Measurement of Coagulum Content]
[0314] A latex containing a specific one of the rubbery polymers
(A-III-1) to (A-III-10) and the graft copolymers (B-III-1) to
(B-III-10) was filtered through a 100-mesh metal screen. Coagulum
remaining on the 100-mesh metal screen was dried. The mass of the
dried coagulum was measured. The ratio (mass %) of the mass of the
coagulum to the mass of the specific one of the rubbery polymers
(A-III-1) to (A-III-10) and the graft copolymers (B-III-1) to
(B-III-10) was calculated. The smaller the coagulum content, the
higher the production stability of the latex of the specific one of
the rubbery polymers (A-III-1) to (A-III-10) and graft copolymers
(B-III-1) to (B-III-10).
Production of (Meth)Acrylate
Production Example: Decyl Acrylate
[0315] Into a 3-Liter four-necked flask equipped with a stirrer,
3.330 parts of para-toluenesulfonic acid used as a catalyst, 100
parts of acrylic acid, 333 parts of decyl alcohol, 0.2 parts of
methoquinone used as a polymerization inhibitor, and 366 parts of
cyclohexane used as a dehydration solvent were charged. The
resulting mixture was stirred in the stream of air. The mixture was
then heated to 88.degree. C. to reflux while stirred. The water
produced in this process was removed. In this process, a sample was
taken from the mixture and analyzed by gas chromatography. The
reaction was terminated when the content of residual alcohol
reached 1% or less.
[0316] After the reaction had been terminated, the reaction mixture
was cleaned with 55 parts of water in order to remove unreacted
acrylic acid and para-toluenesulfonic acid used as a catalyst.
Subsequently, the reaction mixture was cleaned with a 5% aqueous
sodium hydroxide solution in order to further remove unreacted
acrylic acid.
[0317] In order to remove alkali included in the system, the
reaction mixture that had been treated in the above manner was
further cleaned with water. After it had been confirmed that the
reaction mixture changed to substantially neutral, the reaction
mixture was heated to 70.degree. C. at a reduced pressure in order
to remove cyclohexane. Hereby, decyl acrylate was prepared.
[0318] The (meth)acrylates described in Tables 5A and 5B were
prepared as in the preparation of decyl acrylate above, except that
the (meth)acrylic acid and alcohol used were changed, and desired
(meth)acrylates were prepared.
Production of Rubbery Polymer
Example III-i-1: Production of Rubbery Polymer (A-III-1)
[0319] A rubbery polymer (A-III-1) was produced using the following
materials.
[Materials]
TABLE-US-00017 [0320] n-Butyl acrylate 97.5 parts Decyl acrylate
2.5 parts Dipotassium alkenyl succinate 0.2 parts Allyl
methacrylate 0.2 parts 1,3-Butylene dimethacrylate 0.5 parts
Dilauroyl peroxide 0.4 parts Distilled water 406 parts
[0321] Distilled water, n-butyl acrylate, decyl acrylate,
dipotassium alkenyl succinate, allyl methacrylate, 1,3-butylene
dimethacrylate, and dilauroyl peroxide were charged into a reactor
equipped with a reagent injector, a condenser, a jacket heater, and
a stirrer. The resulting mixture was subjected to an ultrasonic
wave treatment using ULTRASONIC HOMOGENIZER US-600 produced by
NIHONSEIKI KAISHA LTD. with an amplitude of 35 .mu.m at room
temperature for 20 minutes to form a pre-emulsion (a-III-1). The
volume-average particle size of the resulting latex was 330 nm.
[0322] The pre-emulsion (a-III-1) was heated to 60.degree. C. in
order to initiate radical polymerization. The liquid temperature
was increased to 78.degree. C. as a result of the polymerization of
the acrylate component. The temperature was maintained to be
75.degree. C. for 30 minutes in order to complete the
polymerization of the acrylate component. The amount of time
required by the production was 90 minutes. Hereby, a latex
containing a rubbery polymer (A-III-1) having a solid content of
18.3%, a coagulum content of 0.8%, and a volume-average particle
size of 330 nm was prepared.
Examples III-i-2 to III-i-7 and Comparative Examples III-i-1 and
III-i-2: Production of Rubbery Polymer (A-III-2) to (A-III-9)
[0323] Latexes each of which contained a specific one of the
rubbery polymers (A-III-2) to (A-III-9) were prepared as in Example
III-i-1, except that the alkyl (meth)acrylates described in Tables
5A and 5B were used instead.
Comparative Example III-i-3: Production of Rubbery Polymer
(A-III-10)
[0324] A rubbery polymer (A-III-10) was produced using the
following materials.
[0325] [Materials]
TABLE-US-00018 n-Butyl acrylate 100 parts Allyl methacrylate 0.2
parts 1,3-Butylene dimethacrylate 0.5 parts t-Butyl hydroperoxide
0.25 parts Ferrous sulfate 0.0002 parts Sodium formaldehyde
sulfoxylate 0.33 parts Disodium ethylenediaminetetraacetate 0.0004
parts Dipotassium alkenyl succinate 0.2 parts Distilled water 406
parts
[0326] Distilled water, 0.2 parts of dipotassium alkenyl succinate,
30 parts of n-butyl acrylate, 0.06 parts of allyl methacrylate,
0.15 parts of 1,3-butylene dimethacrylate, and 0.05 parts of
t-butyl hydroperoxide were charged into a nitrogen-purged reactor
equipped with a reagent injector, a condenser, a jacket heater, and
a stirrer. After the temperature had been increased to 60.degree.
C., ferrous sulfate, sodium formaldehyde sulfoxylate, and disodium
ethylenediaminetetraacetate were added to the reactor. The
resulting mixture was reacted for 60 minutes. Then, a liquid
mixture of 70 parts of n-butyl acrylate, 0.14 parts of allyl
methacrylate, 0.35 parts of 1,3-butylene dimethacrylate, and 0.2
parts of t-butyl hydroperoxide was added dropwise to the reactor
with a pump over 300 minutes. The temperature was increased to
80.degree. C. After the addition of the liquid mixture had been
completed, the temperature was maintained to be 70.degree. C. for
30 minutes in order to complete the polymerization of the acrylate
component. Hereby, a latex containing a rubbery polymer (A-III-10)
was prepared. The amount of time required for producing the latex
was 420 minutes. The latex containing the rubbery polymer
(A-III-10) had a solid content of 18.0%, a coagulum content of
1.2%, and a volume-average particle size (X) of 300 nm.
[0327] Tables 5A and 5B summarize the production time, coagulum
content, volume-average particle size (X), upper-frequency boundary
10%-volume particle size (Y), and lower-frequency boundary
10%-volume particle size (Z) of each of the rubbery polymers.
TABLE-US-00019 TABLE 5A Example Example Example Example Example
Example Example III-i-1 III-i-2 III-i-3 III-i-4 III-i-5 III-i-6
III-i-7 Rubbery polymer A-III-1 A-III-2 A-III-3 A-III-4 A-III-5
A-III-6 A-III-7 Alkyl Amount of 97.5 97.5 97.5 97.5 97.5 97.5 97.5
(meth) n-butyl acrylate acrylate used (part) Other Type Decyl
Tridecyl Stearyl Docosyl Ceryl Lauryl Stearyl (meth) acrylate
acrylate acrylate acrylate acrylate methacrylate methacrylate
acrylate Number of 13 16 21 25 29 15 22 carbon atoms Amount used
2.5 2.5 2.5 2.5 2.5 2.5 2.5 (part) Production time (min) 90 90 90
90 90 90 90 Coagulum content (%) 0.8 0.4 0 0.2 0.8 0.4 0
Volume-average particle size 330 310 300 300 330 310 300 (X) (nm)
Upper-frequency boundary 580 530 420 430 580 540 430 10%-volume
particle size (Y) (nm) Lower-frequency boundary 150 160 180 170 140
160 190 10%-volume particle size (Z) (nm) Remarks For Examples
(acrylates) For Examples (methacrylates)
TABLE-US-00020 TABLE 5B Comparative Comparative Comparative example
example example III-i-1 III-i-2 III-i-3 Rubbery polymer A-III-8
A-III-9 A-III-10 Alkyl Amount of 97.5 97.5 100 (meth) n-butyl
acrylate acrylate used (part) Other Type Octyl Melissyl -- (meth)
acrylate acrylate acrylate Number of 11 33 -- carbon atoms Amount
2.5 2.5 0 used (part) Production time (min) 90 90 420 Coagulum
content(%) 3.1 2.3 1.2 Volume-average particle size 360 340 300 (X)
(nm) Upper-frequency boundary 690 630 510 10%-volume particle size
(Y) (nm) Lower-frequency boundary 120 140 90 10%-volume particle
size (Z) (nm) Remarks For Comparative examples
Production and Evaluations of Graft Copolymer
Example III-ii-1: Production of Graft Copolymer (B-III-1)
[0328] Raw materials were charged into a reactor equipped with a
reagent injector, a condenser, a jacket heater, and a stirrer in
the amounts described below. After the inside of the reactor had
been purged with nitrogen to a sufficient degree, the inside
temperature of the reactor was increased to 70.degree. C. while the
inside of the reactor was stirred.
[0329] [Materials]
TABLE-US-00021 Water (including water contained in the rubbery
polymer 230 parts latex) Latex of the rubbery polymer (A-III-1) 50
parts (as solid content) Dipotassium alkenyl succinate 0.5 parts
Sodium formaldehyde sulfoxylate 0.3 parts Ferrous sulfate 0.001
parts Disodium ethylenediaminetetraacetate 0.003 parts
[0330] Subsequently, a liquid mixture containing acrylonitrile
(AN), styrene (ST), and t-butyl hydroperoxide in the amounts below
was added dropwise to the reactor over 100 minutes, while the
temperature was increased to 80.degree. C.
[0331] [Materials]
TABLE-US-00022 Acrylonitrile 12.5 parts Styrene 37.5 parts t-Butyl
hydroperoxide 0.2 parts
[0332] After the addition of the liquid mixture had been completed,
the temperature was maintained to be 80.degree. C. for 30 minutes
and subsequently reduced. Hereby, a latex containing a graft
copolymer (B-III-1) was prepared. The latex of the graft copolymer
(B-III-1) had a solid content of 29.7%, a coagulum content of 0.1%,
and a volume-average particle size of 370 nm.
[0333] Then, 100 parts of a 1.5% aqueous sulfuric acid solution was
heated to 80.degree. C. While the aqueous solution was stirred, 100
parts of the latex containing the graft copolymer (B-III-1) was
gradually added dropwise to the aqueous solution in order to
solidify the graft copolymer (B-III-1). Subsequently, the
temperature was further increased to 95.degree. C. and maintained
to be 95.degree. C. for 10 minutes.
[0334] The resulting solid was dehydrated, cleaned, and dried.
Hereby, a powdery graft copolymer (B-III-1) was prepared.
Examples III-ii-2 to III-ii-7 and Comparative Examples III-ii-1 to
III-ii-3: Production of Graft Copolymers (B-III-2) to
(B-III-10)
[0335] Graft copolymers (B-III-2) to (B-III-10) were prepared as in
Example III-ii-1, except that the latexes each of which contained a
specific one of the rubbery polymers (A-III-2) to (A-III-10) were
used instead of the latex of the rubbery polymer (A-III-1). Tables
6A and 6B summarize the volume-average particle sizes and coagulum
content of each of the graft copolymers (B-III-2) to
(B-III-10).
[0336] <Production of Thermoplastic Resin Composition>
[0337] With 40 parts of a specific one of the graft copolymers
(B-III-1) to (B-III-10), 60 parts of an acrylonitrile-styrene
copolymer ("UMG AXS Resin S102N" produced by UMG ABS, LTD.), which
was produced by suspension polymerization, was mixed using a
Henschel mixer. The resulting mixture was charged into an extruder
heated at 240.degree. C. and kneaded to form a pellet.
[0338] <Preparation of Test Piece>
[0339] The pellet of the thermoplastic resin composition was molded
into a shape using a four-ounce injection molding machine (produced
by The Japan Steel Works, LTD.) under the following conditions:
cylinder temperature: 240.degree. C., metal mold temperature:
60.degree. C., injection rate: 20 g/sec. Hereby, a rod-like molded
body 1 having a length of 80 mm, a width of 10 mm, and a thickness
of 4 mm was prepared.
[0340] In the same manner as described above, the pellet of the
thermoplastic resin composition was molded into a shape under the
following conditions: cylinder temperature: 240.degree. C., metal
mold temperature: 60.degree. C., injection rate: 20 g/sec. Hereby,
tabular molded bodies 2 having a length of 100 mm, a width of 100
mm, and a thickness of 2 mm were prepared.
[0341] <Evaluations>
(Measurement of Charpy Impact Strength)
[0342] The Charpy impact strength of the molded body 1 was measured
at 23.degree. C. and -30.degree. C. in accordance with ISO 179.
[0343] (Measurement of Melt Volume Rate (MVR))
[0344] The MVR of the pellet of the thermoplastic resin composition
was measured under the conditions of 220.degree. C.-98N in
accordance with ISO 1133. The MVR of the pellet is a measure of the
fluidity of the thermoplastic resin composition.
[0345] (Appearance)
[0346] Five molded bodies 2 were inspected with an optical
microscope (magnification: 200 times), and the total number of
coagulum particles having a size of 100 .mu.m or more was counted.
An evaluation was made in accordance with the following criterion.
A molded body 2 evaluated as ".largecircle." or ".circle-w/dot."
was considered to have good appearance.
[0347] .circle-w/dot.: The number of coagulum particles having a
size of 100 .mu.m or more was 0 to 5.
[0348] .largecircle.: The number of coagulum particles having a
size of 100 .mu.m or more was 6 to 20.
[0349] x: The number of coagulum particles having a size of 100
.mu.m or more was 21 or more.
[0350] Tables 6A and 6B summarize the evaluation results.
TABLE-US-00023 TABLE 6A Example Example Example Example Example
Example Example III-ii-1 III-ii-2 III-ii-3 III-ii-4 III-ii-5
III-ii-6 III-ii-7 Graft Type of B-III-1 B-III-2 B-III-3 B-III-4
B-III-5 B-III-6 B-III-7 copolymer graft copolymer Rubbery polymer/
50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/ 50/12.5/
AN/ST (part) 37.5 37.5 37.5 37.5 37.5 37.5 37.5 Volume-average 370
350 340 340 360 350 340 particle size (nm) Coagulum content (%) 0.1
0.05 0.01 0.01 0.08 0.08 0.01 Rubbery Type A-III-1 A-III-2 A-III-3
A-III-4 A-III-5 A-III-6 A-III-7 polymer Alkyl Amount of 97.5 97.5
97.5 97.5 97.5 97.5 97.5 (meth) n-butyl acrylate acrylate used
(part) Other Type Decyl Tridecyl Stearyl Docosyl Ceryl Lauryl
Stearyl (meth) acrylate acrylate acrylate acrylate acrylate
methacrylate methacrylate acrylate Number of 13 16 21 25 29 15 22
carbon atoms Amount used 2.5 2.5 2.5 2.5 2.5 2.5 2.5 (part)
Evaluation Charpy impact 23.degree. C. 10 11 15 12 10 10 15 results
strength -30.degree. C. 3 3 5 3 3 3 5 (kJ/m.sup.2) MVR 30 29 28 28
29 29 28 (cm.sup.3/10 min) Appearance .largecircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. .largecircle.
.circleincircle.
TABLE-US-00024 TABLE 6B Comparative Comparative Comparative example
example example III-ii-1 III-ii-2 III-ii-3 Graft Type of B-III-8
B-III-9 B-III-10 copolymer graft copolymer Rubbery polymer/
50/12.5/ 50/12.5/ 50/12.5/ AN/ST (part) 37.5 37.5 37.5
Volume-average 400 390 320 particle size (nm) Coagulum content (%)
0.4 0.3 0.3 Rubbery Type A-III-8 A-III-9 A-III-10 polymer Alkyl
Amount of 97.5 97.5 100 (meth) n-butyl acrylate acrylate used
(part) Other Type Octyl Melissyl -- (meth) acrylate acrylate
acrylate Number of 11 33 -- carbon atoms Amount used 2.5 2.5 0
(part) Evaluation Charpy impact 23.degree. C. 9 9 6 results
strength -30.degree. C. 2 2 1 (kJ/m.sup.2) MVR 30 30 18
(cm.sup.3/10 min) Appearance x x x
[0351] The results obtained in Examples and Comparative examples
confirm the following facts.
[0352] Since the graft copolymers (B-III) prepared in Examples
III-ii-1 to III-ii-7 had a small coagulum content, the
thermoplastic resin compositions including the graft copolymers
(B-III) were excellent in terms of impact resistance, fluidity, and
appearance.
[0353] The thermoplastic resin compositions prepared in Comparative
examples III-ii-1 to III-ii-3 were poor in terms of coagulum
content after polymerization, impact resistance, fluidity, or
appearance. Specifically, in Comparative examples III-ii-1 and
III-ii-2, where the number of carbon atoms included in the alkyl
(meth)acrylate was outside the range of the third invention, a
sufficient miniemulsion was not formed and a large amount of
coagulum resulting from coarse particles were formed after
polymerization. This resulted in poor productivity. In addition,
the molded article had poor appearance due to the coagulum
remaining in the molded article. In Comparative example III-ii-3,
where miniemulsion polymerization was not performed, a large amount
of coagulum was formed after polymerization due to the coagulation
of small particles. This resulted in poor productivity. Moreover,
the small particles degraded moldability and impact resistance. In
addition, the coagulum remaining in the molded article degraded the
appearance of the molded article.
INDUSTRIAL APPLICABILITY
[0354] A molded article produced using the thermoplastic resin
composition according to the first invention which includes the
graft copolymer (B-I) according to the first invention has good
impact resistance, good moldability, and good continuous
moldability. Since the molded article achieves good impact
resistance, good moldability, and good continuous moldability in a
much more balanced manner than molded articles produced using known
thermoplastic resin compositions, the thermoplastic resin
composition according to the first invention and a molded article
produced using the thermoplastic resin composition are highly
valuable for use as various industrial materials.
[0355] According to the second invention, it is possible to produce
a graft copolymer (B-II) having excellent storage stability with
good production stability.
[0356] A molded article produced using a thermoplastic resin
composition that includes the graft copolymer (B-II) according to
the second invention has good impact resistance and good
moldability. Since the molded article achieves good impact
resistance and good moldability in a much more balanced manner than
molded articles produced using known thermoplastic resin
compositions, the thermoplastic resin composition according to the
second invention and a molded article produced using the
thermoplastic resin composition are highly valuable for use as
various industrial materials.
[0357] A molded article produced using the thermoplastic resin
composition according to the third invention which includes the
graft copolymer (B-III) according to the third invention has good
impact resistance and good appearance. Since the molded article
achieves good impact resistance and good appearance in a much more
balanced manner than molded articles produced using known
thermoplastic resin compositions, the thermoplastic resin
composition according to the third invention and a molded article
produced using the thermoplastic resin composition are highly
valuable for use as various industrial materials.
[0358] Although the present invention has been described in detail
with reference to particular embodiments, it is apparent to a
person skilled in the art that various modifications can be made
therein without departing from the spirit and scope of the present
invention.
[0359] The present application is based on Japanese Patent
Application No. 2016-009798 filed on Jan. 21, 2016, and Japanese
Patent Application Nos. 2016-062085 and 2016-062086 filed on Mar.
25, 2016, which are incorporated herein by reference in their
entirety.
REFERENCE SIGNS LIST
[0360] 10 METAL MOLD [0361] 11 SPRUE [0362] 12, 13 RUNNER [0363]
14, 15 SIDE GATE [0364] 20 MOLTEN RESIN
* * * * *